Information and Ideas

In his sociological studies, Ray Oldenburg coined the term "third place" to describe public spaces, such as coffee shops, libraries, and hair salons, that are distinct from the home ("first place") and the workplace ("second place"). Oldenburg argued that these environments are crucial for civil society, hosting regular, voluntary, and informal gatherings that foster community cohesion. While modern urban planners often prioritize economic optimization, leaving little room for non-commercial public spaces, contemporary research suggests that the erosion of these third places correlates with a decline in social trust and civic engagement. Thus, maintaining accessible third places is not merely a matter of urban convenience, but is vital for sustaining the democratic fabric of communities.

Which choice best states the main idea of the text?

In temperate forests, the decomposing leaves of deciduous trees typically release nutrients, such as nitrogen, back into the soil, promoting the growth of surrounding understory plants. However, in forests dominated by the invasive tree species *Ailanthus altissima* (tree of heaven), the dropped leaves contain high levels of ailanthone, a natural herbicide. Researchers have observed that understory plant diversity is significantly lower in areas colonized by *A. altissima* than in areas dominated by native deciduous trees. Since native plants in these forests rely on soil nutrients but are highly sensitive to chemical inhibitors, this suggests that Which choice most logically completes the text?

In a 2026 study of medieval European manuscripts, conservator Dr. Marcus Thorne and his team evaluated the efficacy of calcium hydroxide nanoparticles dispersed in short-chain alcohols for neutralising acid in historical inks. The researchers applied the dispersion to several fifteenth-century parchment folios that exhibited iron gall ink corrosion. The treatment successfully stabilised the cellulose matrix and neutralised active acids without altering the structural integrity of the parchment's collagen fibers. However, the team noted that the nanoparticles formed a thin, white crystalline haze on the surface of areas with dense carbon-based black ink deposits, whereas areas written with iron gall ink remained visually unaltered.

According to the text, which statement is true about the effects of the nanoparticle treatment on the parchment folios?

In many temperate forest ecosystems, the understory fern *Dryopteris carthusiana* accumulates high concentrations of manganese ($Mn$), a metal toxic to most competing angiosperms, in its senescent fronds. Researchers hypothesized that this accumulation acts as an 'allelochemical filter'—when the fronds decay, the released $Mn$ increases soil toxicity, suppressing the germination of neighboring seedlings. However, in soils rich in organic matter, $Mn$ readily binds to humic acids, forming stable complexes that render the metal biologically unavailable to plants. In contrast, in sandy, organic-poor soils, $Mn$ remains highly mobile and soluble. Which choice most logically completes the text?

Ornithologist Dr. Marcus Thorne studied the song patterns of the white-crowned sparrow (*Zonotrichia leucophrys*) in different environments. Thorne hypothesized that sparrows living in urban areas sing at a higher pitch (minimum frequency) than those in rural areas to prevent their songs from being drowned out by low-frequency city noise. Which finding, if true, would most directly support Thorne's hypothesis?

In bioacoustics, the acoustic niche hypothesis suggests that vocalizing animals occupy distinct frequency bands and temporal slots within a habitat to prevent their signals from being masked by competing sounds. Similar to how radio stations operate on separate frequencies to avoid interference, species in a healthy ecosystem adjust the pitch, timing, and structure of their calls. In highly degraded environments, however, this acoustic partitioning often collapses as invasive noises disrupt the established channels, forcing species to compete directly for auditory space. Consequently, biophonic structure serves as a crucial indicator of ecological health, reflecting the degree of cooperative organization within a habitat's animal community. Which choice best states the main idea of the text?

Glaciologist Dr. Hiroshi Tanaka investigated the impact of windborne dust on glacier melting in the Southern Alps. Tanaka hypothesized that dust particles originating from neighboring agricultural fields deposit onto glacier surfaces, lowering the glaciers' albedo—their capacity to reflect solar radiation—and consequently accelerating surface melting during the summer. To test this hypothesis, Tanaka's team monitored several glaciers, measuring both surface dust concentration and reflectivity alongside local temperature changes. Which choice, if true, would most directly support Tanaka's hypothesis?

Leafcutter ants (*Atta cephalotes*) do not eat the leaves they harvest. Instead, they transport the cut vegetation to subterranean nests, where they use it as a substrate to cultivate a specific species of fungus (*Leucoagaricus gongylophorus*). The ants feed exclusively on this cultivated fungus, which in turn relies on the fresh leaves brought by the ants for its growth. The relationship is mutually beneficial, as the fungus provides nutrition for the ants, and the ants provide a steady supply of nutrients and protect the fungus from harmful pathogens. According to the text, what do leafcutter ants use the harvested leaves for?

Sociologist Dr. Clara Vance and her team investigated the impact of community gardens on neighborhood cohesion in urban areas. Vance hypothesized that neighborhoods with active community gardens experience higher levels of social interaction among residents than neighborhoods without such gardens. Which finding, if true, would most directly support Vance's hypothesis?

Ecologist Dr. Nia Mshila and colleagues investigated the phenotypic plasticity of the marine snail *Nucella lapillus* in response to predatory cues from the green crab *Carcinus maenas*. In calm waters, snails exposed to crab effluents typically develop significantly thicker shells to resist crushing. However, Mshila hypothesized that in habitats characterized by high wave action, *N. lapillus* will prioritize shell shape (developing a wider aperture for stronger foot attachment to rocks) over shell thickness, even when exposed to crab cues, because hydrodynamic dislodgement poses a more immediate survival threat than predation. Which finding, if true, would most directly support Mshila's hypothesis?

Ancient Roman marine concrete has survived for over two millennia in seawater, whereas modern concrete degrades within decades under similar conditions. Researchers found that the Romans mixed volcanic ash and lime with seawater, forming a mineral called aluminous tobermorite. This mineral crystallizes within the concrete, strengthening the structure over time and preventing cracks. Because modern concrete lacks volcanic ash, it does not form this mineral when exposed to seawater. Therefore, the exceptional durability of Roman marine concrete is largely attributable to ______

Which choice most logically completes the text?

In temperate rainforests, fallen trees, or 'nurse logs,' serve a critical role in forest regeneration. As these large logs decay on the forest floor, they accumulate moisture and nutrients, providing a hospitable substrate for seedlings, particularly Western hemlock. This substrate is especially vital because the dense moss and organic debris on the forest floor often prevent seeds from making contact with the mineral soil, leading to high seedling mortality. By germinating on nurse logs, seedlings can access light and avoid pathogens residing in the forest floor soil. Thus, nurse logs act as essential nurseries that facilitate the survival and growth of new trees, shaping the structural diversity of the forest over time.

Which choice best states the main idea of the text?

The sociable weaver (*Philetairus socius*), a bird species native to Southern Africa, constructs the largest nests of any bird. These communal structures, which can house up to one hundred nesting pairs, are built primarily from twigs, dry grass, and straw. Researchers have observed that the inner chambers of these nests retain heat during cold desert nights, maintaining a temperature significantly higher than the ambient air outside. Furthermore, the birds populate the central chambers of the nest first because these areas provide the greatest insulation against the cold, whereas the outer chambers are occupied only when the inner chambers are fully populated.

According to the text, which statement is true about the nesting behavior of the sociable weaver?

Sociologist Dr. Evelyn Choi investigated the relationship between 'third places'—communal spaces separate from home and work—and community resilience in urban neighborhoods. Choi hypothesized that neighborhoods containing third places that facilitate regular, active interaction among different age groups (such as multigenerational community gardens) exhibit greater social cohesion during environmental crises than neighborhoods with third places that cater primarily to a single demographic group (such as youth centers or senior clubs). Which finding, if true, would most directly support Choi's hypothesis?

In a study of deep-sea hydrothermal vents in the Mariana Trench, marine biologist Dr. Elena Rostova and her team analyzed the metabolic pathways of the newly discovered chemolithoautotrophic bacterium *Sulfurimonas maris*. The researchers found that unlike related species from shallower vents that rely exclusively on hydrogen oxidation, *Sulfurimonas maris* possesses genes encoding both hydrogenases and enzymes for the oxidation of thiosulfate. However, laboratory assays showed that the bacterium only expresses the thiosulfate oxidation genes when local concentrations of dissolved oxygen drop below a specific threshold of $5\text{ micromoles per liter}$. This genetic adaptation allows *Sulfurimonas maris* to maintain energy production in highly fluctuating oxygen zones near the vent chimney.

Based on the text, what is true of the expression of thiosulfate oxidation genes in *Sulfurimonas maris*?

Botanist Dr. Elena Torres investigated how desert wildflowers adapt to drought conditions to ensure pollination. Torres claimed that when soil moisture levels are low, these wildflowers produce a stronger scent to attract pollinators from further away. Which choice, if true, most directly supports Torres's claim?

Moon jellyfish (*Aurelia aurita*) thrive in warmer ocean waters, which speed up their reproduction. However, warmer water also contains less dissolved oxygen, which jellyfish need to survive. While modest temperature increases cause jellyfish populations to grow, extreme temperature increases deplete oxygen to levels that limit jellyfish survival. Thus, in areas experiencing extreme ocean warming, moon jellyfish populations will likely

Which choice most logically completes the text?

The resurrection plant (*Selaginella lepidophylla*) is a desert dweller renowned for its ability to survive extreme dehydration. During prolonged dry spells, the plant curls its stems into a tight, brown ball, entering a dormant state that minimizes water loss. When exposed to moisture, the stems uncurl and regain their green color, a process that can occur in as little as three hours. However, this rehydration is purely mechanical; the plant does not resume active growth until its root system is fully re-established in moist soil.

Based on the text, what is true of the resurrection plant during dry spells?

Marine biologist Dr. Teresa Rossi and colleagues investigated the acoustic behavior of humpback whales (*Megaptera novaeangliae*) during foraging. The team hypothesized that humpback whales modify the acoustic structure of their "feeding calls" to coordinate cooperative bubble-net feeding only when the local density of their prey (krill) falls below a specific threshold. According to the researchers, this acoustic modification serves to recruit conspecifics and organize group foraging to optimize efficiency under scarce resource conditions, whereas in areas of high prey density, whales forage individually without using these modified calls.

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

Archaeologist Dr. Sofia Al-Jamil and her team investigated the dietary habits of the ancient Maya during the Terminal Classic period (c. 800–900 CE) at the site of Ucanal. Al-Jamil hypothesized that during periods of prolonged drought, the population shifted their primary crop consumption from maize (*Zea mays*), which is highly drought-sensitive, to more drought-resistant wild tubers and root crops. Which choice, if true, would most directly support the team's hypothesis?