All practice questions

Marine biologist Dr. Clara Silva investigated the impact of offshore wind farms on local benthic communities. Silva hypothesized that the artificial structures (the turbine foundations) serve as artificial reefs, attracting specific filter-feeding species like the blue mussel (*Mytilus edulis*) and subsequently increasing the density of their predators, such as the common starfish (*Asterias rubens*), on and immediately adjacent to the structures compared to surrounding sandy seabed areas.

Which choice, if true, would most directly support Silva's hypothesis?

Astronomers studying the interstellar medium often focus on cosmic dust clouds, which absorb and scatter visible light from distant stars. By blocking this starlight, the dust clouds make it difficult to observe the structures behind them using optical telescopes. To overcome this obstacle, researchers utilize infrared telescopes, which can detect longer wavelengths of light that pass through the dust relatively unimpeded. Consequently, this technology has allowed scientists to map previously hidden regions of our galaxy, revealing new star-forming clusters and nebulae.

Which choice best describes the function of the underlined sentence in the text as a whole?

Marine biologist Dr. Clara Vance and her team investigated how ocean acidification affects the shell-building behavior of the marine snail *Anachis avarosa*. The team exposed groups of snails to either current seawater pH levels or lower pH levels simulating projected ocean acidification. While overall calcification rates declined in the low-pH environment, Vance hypothesized that *Anachis avarosa* selectively allocates its limited calcium carbonate resources to preserve the structural integrity of the shell's apex—which shields vital internal organs—at the expense of the outer body whorl. Which finding from the team's study, if true, would most directly support Dr. Vance's hypothesis?

White clover (*Trifolium repens*) produces hydrogen cyanide (HCN) to deter herbivores, but winter freezing can damage cell membranes, releasing HCN and causing self-poisoning. Consequently, clover populations in colder environments typically exhibit lower rates of HCN production. Although urban areas are generally warmer than rural ones due to the urban heat island effect, researchers in a northern city observed that clover in urban parks where snow was regularly cleared had lower rates of HCN production than clover in undisturbed, snow-covered rural fields nearby. Since snow cover provides thermal insulation that buffers soil from freezing air, which choice most logically completes the text?

If $\frac{x + 5}{x - 1} = 3$, what is the value of $x + 1$?

A student takes the following notes while researching the history of the language Esperanto:

* Esperanto is a constructed international auxiliary language created in 1887 by L. L. Zamenhof.
* Zamenhof designed the language to be easy to learn and politically neutral.
* His primary goal was to foster international understanding and peace.
* Currently, Esperanto is estimated to have up to two million speakers worldwide.

The student wants to summarize the origin and purpose of Esperanto. Which choice most effectively uses information from the given notes to accomplish this goal?

Many historians have argued that the adoption of currency in medieval Europe was driven primarily by merchant guilds seeking to facilitate long-distance trade. However, historian Dr. Evelyn Vance hypothesizes that local, small-scale transactions among peasant farmers played a far more critical role in the widespread adoption of minted coins. Vance claims that the regular usage of coinage was sustained not by high-value international commerce, but by the necessity of resolving micro-debts accrued through everyday mutual aid and agricultural cooperation within rural villages. Which choice, if true, would most directly support Vance's hypothesis?

Many plants growing in arid environments possess trichomes, which are tiny, hair-like structures on the surfaces of their leaves. While early botanists hypothesized that these structures functioned primarily as a physical barrier against herbivorous insects, subsequent studies have revealed a different principal role. Researchers found that trichomes form a dense boundary layer that reflects solar radiation and reduces air movement across the leaf surface. By lowering leaf temperatures and slowing transpiration, trichomes primarily serve to conserve water, allowing plants to survive prolonged droughts.

Which choice best states the main idea of the text?

Literary scholar Dr. Marcus Thorne argues that early twentieth-century modernist poetry in America, though often characterized as detached from daily life, frequently employed metaphors of industrial machinery to evoke intimate human emotions. Thorne contends that these poets used mechanical processes to represent the internal psychological states of their speakers, thereby bridging the divide between the impersonal modern world and personal experience.

Which choice, if true, would most directly support Thorne's argument?

In a study of remote workplace dynamics, organizational psychologist Dr. Valeria Rossi investigated the impact of 'micro-rewards'—small, digital tokens of recognition—on employee performance. Rossi hypothesized that while these rewards initially increase engagement, their frequent use eventually undermines intrinsic motivation, particularly for complex, creative tasks. However, she proposed that this negative effect is mitigated when the rewards are peer-nominated rather than system-generated, as peer recognition reinforces a sense of social connectedness that sustains motivation. Which choice, if true, would most directly support Rossi's hypothesis?

In marine ecosystems, kelp forests provide critical habitat for numerous marine organisms. However, these vital habitats are frequently threatened by sea urchins, which consume kelp at a rapid rate. Sea otters play a crucial role in maintaining the balance of these ecosystems by preying on sea urchins, thereby preventing the overgrazing of kelp forests. Without sea otters, kelp forests would quickly collapse, leading to a significant loss of biodiversity in the region. Thus, the presence of sea otters is essential to the health and stability of the entire coastal marine ecosystem.

Which choice best states the main purpose of the text?

In modern agricultural science, cover crops are often planted to prevent soil erosion during the winter off-season. Some researchers have suggested that these crops also actively enrich the soil microbiome. To test this hypothesis, agricultural scientist Dr. Helena Lin monitored soil microbial diversity in experimental fields planted with clover cover crops versus unplanted fallow fields. Lin observed a significant increase in beneficial bacterial populations in the clover-planted soil. She concluded that cover crops do indeed enhance the microbiome, thereby improving soil health for subsequent cash crops.

Which choice best describes the overall structure of the text?

Elephants are known for their complex social structures and deep family bonds, which require constant communication over long distances. While they make many sounds that are audible to humans, such as trumpets and rumbles, they also utilize infrasound—low-frequency vibrations that travel through the ground and air. These signals, which are below the range of human hearing, can travel for several miles, allowing separated herds to coordinate their movements and avoid potential dangers. By monitoring these vibrations through their sensitive feet and ears, elephants maintain a cohesive network even when they are out of sight.

Which choice best states the main idea of the text?

Companion planting is the agricultural practice of growing different crop species in close proximity to benefit one or both plants. Some researchers hypothesize that planting marigolds (*Tagetes*) alongside tomato plants (*Solanum lycopersicum*) protects the tomatoes from root-knot nematodes—microscopic pests that damage tomato root systems and reduce fruit yields. To test this hypothesis, the researchers compared tomato plants grown in fields with marigolds to tomato plants grown in fields without marigolds.

Which choice, if true, would most directly support the researchers' hypothesis?

Blue jays (*Cyanocitta cristata*) play a crucial role in the expansion of oak forests across North America. During the autumn months, these birds gather thousands of acorns, burying them in various underground caches to secure food for the winter. While blue jays retrieve many of these stored acorns, they inevitably leave a significant portion recovery-free. These forgotten acorns, buried in favorable soil conditions far from the parent trees, frequently germinate and grow into new oak trees. Consequently, the caching behavior of blue jays is essential for the dispersal and regeneration of oak populations.

Which choice best states the main idea of the text?

Historians have long believed that the ancient city of Teotihuacán was governed by a single powerful ruler, pointing to large monuments dedicated to leadership. However, archaeologist Linda Manzanilla proposed that the city was actually governed by a co-ruling council of representatives from different neighborhoods. She excavated multi-family apartment compounds and found evidence of shared resources rather than elite palaces. This discovery supports the idea that collective governance was central to the city's political structure.

Which choice best describes the function of the underlined sentence in the text as a whole?

Cover crops such as crimson clover are frequently utilized to manage soil quality in agricultural ecosystems. Crimson clover has the capacity to fix nitrogen, an essential element for plant growth, into the soil. To evaluate this effect, researchers compared soil plots planted with crimson clover to plots that remained fallow. Their analysis revealed that the plots with clover exhibited significantly higher nitrogen concentrations. Given that the growth of subsequent crops is highly dependent on the availability of soil nitrogen, this outcome suggests that planting crimson clover between cash crop seasons ______

Which choice most logically completes the text?

In many alpine plants, the synthesis of anthocyanin pigments is upregulated in response to intense ultraviolet-B (UV-B) radiation, serving as a photoprotective shield. Biologists hypothesized that this response is purely plastic, triggered solely by direct exposure. However, in a recent study, researchers grew offspring of alpine plant populations under uniform, low-UV-B greenhouse conditions. Offspring whose parents had experienced high wild UV-B exhibited significantly higher baseline anthocyanin levels than did offspring of parents from low-UV-B environments, despite neither offspring group encountering UV-B. Which choice most logically completes the text?

In 1856, chemist William Henry Perkin was attempting to synthesize quinine, a treatment for malaria, in his home laboratory. During his experiments, Perkin oxidized aniline, which resulted in a dark, sticky residue. When he cleaned the flask with alcohol, the residue dissolved to produce a vibrant purple solution. This substance, which he named mauveine, became the world's first commercially successful synthetic dye. Perkin patented the process and established a factory to manufacture the dye, transforming both the textile industry and the field of industrial chemistry.

Based on the text, what is true about William Henry Perkin's discovery of mauveine?

Marine biologist Dr. Elena Rostova and colleagues investigated the resilience of giant kelp (*Macrocystis pyrifera*) to marine heatwaves. Some researchers hypothesize that kelp forests situated near deep-water submarine canyons are more resilient to ocean warming than those along shallow continental shelves because these canyons facilitate the upwelling of cool, nutrient-rich subsurface water, shielding the kelp from warm surface temperatures. Rostova’s team monitored kelp canopy health at several canyon-adjacent and shelf-adjacent sites during a major heatwave.

Which finding from Rostova’s study, if true, would most directly support the researchers' hypothesis?