Topic Development

Passage:

[1] Modern engineers have long marveled at the durability of ancient Roman concrete structures, which have survived for millennia in harsh environments. [2] Recent chemical analyses reveal that the secret lies in "lime clasts," small white mineral chunks previously dismissed as evidence of poor craftsmanship. [3] When cracks begin to form in the concrete, water seeping into the fissures dissolves the calcium within these clasts. [4] This dissolved calcium then recrystallizes, effectively sealing the cracks and preventing further structural damage.

The writer wants to add a sentence after sentence 1 that provides the most specific, concrete evidence of the durability of these ancient structures. Which of the following sentences would best accomplish this goal?

The sentences below are from a draft of an essay about gecko adhesion. Arrange the sentences in the most logical order to support the claim that geckos rely on microscopic structures and physical forces to climb smooth surfaces.

The following is an excerpt from an essay about geological discoveries.

[1]
__________________________________________________ Prior to Danish seismologist Inge Lehmann's groundbreaking publication in 1936, scientists believed that the Earth's core was a single, uniform liquid sphere. By analyzing seismic waves from a major earthquake in New Zealand, Lehmann observed that some P-waves were unexpectedly deflected, or diffracted, deep within the Earth. She reasoned that this deflection could only be caused by a distinct, solid inner core nested inside the liquid outer core. Her hypothesis was eventually confirmed by more advanced instruments, redefining the field of seismology.

Which choice provides the most effective introduction to the paragraph?

Passage

In 1965, chemist Stephanie Kwolek was analyzing synthetic fiber chains at DuPont in search of a lightweight material to reinforce car tires. During her experiments, she generated a strange, cloudy solution that looked unlike the thick, clear polymers she typically worked with. Rather than discarding the unusual mixture, Kwolek convinced a colleague to run it through a spinneret, a machine used to draw liquid polymers into fibers. The resulting fiber was astonishingly strong—five times stronger than steel on a pound-for-pound basis—and resistant to both heat and corrosion. [1]

DuPont quickly recognized the commercial potential of this new material, trademarking it as Kevlar. In the decades following Kwolek's discovery, Kevlar found applications in racing sails, bicycle tires, and optical fiber cables. Most notably, its high tensile strength and lightweight nature revolutionized personal armor, saving the lives of countless military personnel and law enforcement officers.

Question

The writer wants to add a sentence at the end of the first paragraph (at point [1]) to conclude the discussion of Kwolek’s laboratory discovery and transition to the next paragraph's focus on Kevlar's commercial applications. Which of the following sentences best accomplishes this goal?

[1]
__________________________________________________

[2] While working with Charles Babbage on his plans for the Analytical Engine, a mechanical general-purpose computer, Lovelace translated an article by Italian military engineer Luigi Menabrea. [3] In her translation, which she expanded with an extensive set of notes, she described an algorithm for the Analytical Engine to compute Bernoulli numbers. [4] This algorithm is now widely recognized as the world's first computer program, demonstrating that Lovelace foresaw the machine's capability to process symbolic representations beyond mere numerical calculation.

The writer is considering adding a sentence at the beginning of the passage (before Sentence 2) to introduce the main thesis of the essay. Which of the following sentences would best accomplish this goal?

In the late nineteenth century, socialite Josephine Cochrane grew frustrated with the frequent chipping of her fine china during hand-washing. Resolving to design a mechanical solution, she measured her dishes, constructed wire compartments to hold them secure, and coupled these with a copper boiler and a hand-cranked water pump. Her invention was a success, washing dishes quickly and safely. Cochrane’s design was patented in 1886 and went on to win top honors at the 1893 World's Columbian Exposition.

At first, the commercial dishwasher found its primary market in hotels and restaurants, which valued the machine’s efficiency and sanitation capabilities. However, Cochrane continued to refine her design, envisioning a future where every home would have one. [1]

Which of the following sentences, if added at point [1], would provide the most logical transition and effective conclusion to the passage?

The following is an excerpt from an essay about eighteenth-century zoology.

[1]
_____________________. When the first specimen arrived in England from Australia in 1799, British naturalists were convinced it was a clever hoax. George Shaw, the keeper of natural history at the British Museum, even used a pair of scissors to inspect the dried pelt, searching for the stitches he assumed were binding a duck’s bill to a beaver-like body. However, as more specimens arrived, scientists had to accept that this bizarre creature, with its webbed feet, fur, and venomous spurs, was indeed real.

Which choice most effectively introduces the paragraph and establishes the main topic of the passage?

In the late nineteenth century, Thomas Edison's phonograph introduced the wax cylinder, the first commercial medium for recording and reproducing sound. These fragile cylinders captured invaluable early musical performances, spoken-word recordings, and oral histories. However, because wax degrades rapidly when exposed to humidity and physical playback wears down the grooves, playing these recordings carries a high risk of destroying them forever.

To solve this, researchers developed IRENE, a non-contact optical scanning system that creates ultra-high-resolution digital images of the cylinders' grooves. Software then reconstructs the audio from these digital maps, bypassing the need for physical contact. [1] This non-contact system, that utilizes digital photography, will preserve the fragile cylinders for future generations.

Which choice most effectively concludes the paragraph by emphasizing how the digital scanning technology solves the problem of preserving fragile historical recordings?

A writer is editing a draft of an essay about the discovery of the coelacanth.

In 1938, Marjorie Courtenay-Latimer, a South African museum curator, discovered an unusual fish among the catch of a local trawler. Recognizing its unique features—including lobed fins that resembled limbs—she contacted ichthyologist J.L.B. Smith to help identify it. Smith recognized the specimen as a coelacanth, a member of a lineage believed to have gone extinct 66 million years ago. [1] Prior to this discovery, scientists had only studied the prehistoric fish through fossilized remains. The find, often referred to as the 'living fossil' discovery, completely reshaped scientific understanding of vertebrate evolution.

At this point, the writer is considering adding the following true statement:

Fossils are formed when organic material is slowly replaced by minerals over millions of years.

Should the writer make this addition at point [1]?

[1] __________________________________________________

[2] In 1964, radio astronomers Arno Penzias and Robert Wilson were employing an ultra-sensitive horn antenna at Bell Laboratories to analyze radio signals from the spaces between galaxies. However, their measurements were repeatedly disrupted by a persistent, low-frequency buzz that registered in their receiver. Despite washing the antenna, evicting a nesting pair of pigeons, and rebuilding the electrical components, the static remained completely unchanged. This mysterious hiss, which was eventually recognized as the cosmic microwave background radiation, provided the first concrete evidence of the Big Bang, transforming our understanding of the universe's origin.

Which choice most effectively introduces the passage by establishing its central focus on how a major cosmological breakthrough arose from an unexpected experimental obstacle?

For decades, scholars of Maya hieroglyphs viewed the inscriptions as purely mystical, representing astronomical calendars and religious symbols rather than historical records. This perspective shifted in 1960 when art historian Tatiana Proskouriakoff published a groundbreaking study of the stelae—carved stone slabs—at the site of Piedras Negras. By arranging the monuments chronologically based on their carved dates, she noticed that the life spans of the figures depicted corresponded to average human lifespans, suggesting the carvings actually recorded the histories of rulers.

The writer wants to conclude the paragraph by reinforcing the impact of Proskouriakoff’s discovery on the scholarly understanding of Maya writing. Which choice best accomplishes this goal?

The sentences below are from a draft of an essay about historical preservation. To ensure the paragraph logically builds its claim that optical scanning technologies safely retrieve sound from fragile wax cylinders, arrange the sentences in the most logical order.

In the late nineteenth century, bicycling was a privilege reserved primarily for athletic young men who could navigate the precarious "ordinary" bicycle—popularly known as the penny-farthing. With its massive front wheel and lack of brakes, the penny-farthing was notoriously difficult to mount and prone to sending riders headfirst over the handlebars.

[1] __________________________________________________. This new design featured two wheels of equal size, a steerable front wheel, and a chain drive connected to the rear wheel, making cycling accessible to the general public. As a result, millions of people, particularly women, gained a new sense of independence and mobility.

Given that all the choices are true, which one, if inserted at [1], provides the most effective introduction to the second paragraph and best establishes the focus of the remainder of the passage?

Passage:

In 1964, radio astronomers Arno Penzias and Robert Wilson were using a large horn antenna in Holmdel, New Jersey, to detect weak radio waves bounced off balloon satellites. To their frustration, they kept detecting a persistent, low-level hum in the microwave spectrum that seemed to come from all directions in the sky. They spent months checking their equipment, going so far as to clean out nesting pigeons and their waste from the horn, but the static remained. Ultimately, this mysterious noise was identified not as a technical malfunction, but as the cosmic microwave background radiation—the relic radiation left over from the Big Bang.

The writer wants to add a concluding sentence at the end of the passage to emphasize the significance of the scientists' discovery. Which of the following sentences best accomplishes this goal?

A writer is drafting an essay about concert hall design.

Concert hall design relies heavily on the strategic placement of acoustic clouds—suspended overhead panels that reflect sound waves toward the audience. In large halls, sound traveling directly from the stage can dissipate before reaching the rear seats, resulting in a muffled listening experience. Acoustic clouds solve this by intercepting upward-traveling sound waves and directing them downward. These panels are typically constructed from dense materials like glass-reinforced gypsum or hardwood to ensure they reflect rather than absorb sound. By carefully adjusting the angle and height of these panels, acousticians can customize the sound distribution to suit different musical performances, from intimate chamber ensembles to full orchestras.

The writer is considering deleting the bolded sentence. Should the sentence be kept or deleted?

[1] __________________________________________________

[2] For generations, Western epigraphers had treated Maya hieroglyphs as purely ideographic symbols representing abstract concepts rather than phonetic sounds. This consensus was largely enforced by the prominent archaeologist J. Eric S. Thompson, who dismissed any phonetic interpretations as groundless speculation.

In 1952, Soviet linguist Yuri Knorozov challenged this dogma by publishing a paper proposing that the writing system was logo-syllabic, combining logograms with phonetic syllables. By applying this syllable-based reading to the 16th-century manuscripts of Bishop Diego de Landa, Knorozov successfully decoded glyphs phonetically. This breakthrough ultimately unlocked the rich historical records of the Maya civilization, proving that their writing was a fully functional, spoken language.

Which of the following sentences, if placed at the beginning of the passage (replacing the placeholder [1]), would most effectively introduce the main topic of the passage?

Passage

In the early twentieth century, astronomer Henrietta Swan Leavitt made a groundbreaking discovery while analyzing photographic plates at the Harvard College Observatory. By studying Cepheid variable stars, she established that a star’s intrinsic luminosity is directly related to the period of its pulsations. This relationship became a vital tool, enabling astronomers to calculate the distance to far-off galaxies. Indeed, Edwin Hubble used Leavitt’s law to determine the distance to the Andromeda Nebula, showing that it lay far outside our own galaxy.

Given that all the choices are true, the writer wants to revise the bolded sentence to provide the most specific, concrete details that support the claim that Leavitt's discovery was essential in measuring the vast scale of the universe. Which choice best accomplishes this goal?

In April 1860, the Pony Express began its brief but legendary run, promising to deliver mail across the American West in just ten days. The service relied on a relay system of young riders and fast horses stationed at intervals along a 1,900-mile trail. Riders would gallop from one station to the next, quickly transferring the mailbags to a fresh mount before speeding off again. Despite its fame, the Pony Express was a financial failure and operated for only nineteen months. It was officially rendered obsolete by the completion of the transcontinental telegraph line, which allowed for instantaneous communication.

The writer is considering deleting the underlined sentence from the passage. Should the sentence be kept or deleted?

The following is an excerpt from an essay about automotive safety history.

[1] __________________________________________________ During a winter trip to New York City in 1902, Mary Anderson observed a trolley driver struggling to see through the falling sleet, constantly opening the window to wipe the windshield by hand. This uncomfortable and dangerous practice inspired her to sketch a manual swinging arm with a rubber blade, operated from inside the vehicle. Though trolley companies initially rejected her invention, claiming it would distract drivers, Anderson's design laid the essential foundation for what would eventually become standard safety equipment in all modern automobiles.

Which choice most effectively introduces the paragraph by establishing its main focus?

Early motion pictures were recorded on cellulose nitrate film, a highly flammable material prone to rapid decay. Over time, these silent films deteriorate into a sticky, acidic goo or a highly combustible powder. [1] Consequently, archivists at film preservation centers work tirelessly to copy surviving silent films onto safer, modern polyester stock. However, the process is painstakingly slow and expensive, meaning many historical films are lost forever before they can be saved.

The writer is considering adding the following sentence at Point [1]:

"Cellulose nitrate was also commonly used to manufacture everyday household items, such as combs, toys, and photographic negatives."

Should the writer make this addition?