Strengthen

Paleoclimatologist: Deep-sea core samples from the subpolar Southern Ocean reveal sediment strata from approximately 430,000 years ago containing concurrent spikes in windborne mineral dust and dense accumulations of fossilized Fragilariopsis diatoms. Because bioavailable iron is a documented limiting nutrient for phytoplankton in these waters, researchers concluded that episodic increases in atmospheric dust deposition directly triggered massive surface diatom blooms during that glacial epoch.

Statement: The researchers' conclusion is strengthened if geochemical analysis demonstrates that during the periods when these strata formed, deep-sea bottom currents were not vigorous enough to laterally transport mineral grains and diatom microfossils from distant shallow shelves into the sampling basin.

Economist: To reduce grid strain during heatwaves, a regional power authority enrolled thousands of households in an automated demand-response program that remotely raises home thermostat settings by $2^\circ\text{C}$ during peak afternoon hours, unless a resident manually cancels the adjustment. Although fewer than 15 percent of enrolled households ever overrode the automated adjustments, peak-hour residential electricity consumption across the region fell by only 3 percent, far below the 14 percent reduction predicted by thermodynamic engineering models. Several critics conclude that the engineering models severely overestimated the energy savings of a $2^\circ\text{C}$ temperature increase. However, the models were likely accurate; the shortfall is almost certainly attributable to behavioral pre-cooling, in which residents manually set their thermostats several degrees lower than normal in the late morning before the peak period begins.

Which of the following, if true, most strongly supports the economist's argument?

Economist: To mitigate extreme strain on the regional power grid during summer heatwaves, an energy authority introduced dynamic surge pricing for commercial manufacturers between 1:00 p.m. and 6:00 p.m. Over the subsequent summer, total peak-period electricity drawn from the grid by these manufacturers fell by 22 percent, while their overall production volume remained unchanged. Therefore, the surge pricing policy successfully motivated manufacturers to shift energy-intensive production activities to off-peak nighttime and morning hours.

Which of the following, if true, most strongly supports the economist's conclusion?

Match each of the following arguments with the supplementary finding that provides the strongest logical support for its stated conclusion.

Marine Archaeologist: Bronze artifacts recovered from seventeenth-century shipwrecks often suffer rapid corrosion known as 'bronze disease' when exposed to atmospheric oxygen and humidity. In a recent preservation trial, conservators submerged several newly excavated bronze cannons in a sodium sesquicarbonate solution for six months. Following the treatment, none of the submerged cannons developed active bronze disease during two years of atmospheric exposure. The conservators concluded that the sodium sesquicarbonate wash effectively leaches destructive cuprous chlorides out of ancient bronze, thereby preventing post-excavation corrosion.

Which of the following, if true, most strengthens the conservators' argument?

Archaeologist: Recent excavations at a Middle Pleistocene hominin campsite recovered over two thousand stone cutting flakes. Microscopic analysis of the strike platforms revealed that approximately 88 percent display asymmetric curvature characteristic of intentional detachment by a right-handed knapper. In modern humans, population-level right-handedness reflects left-hemispheric cerebral lateralization—a neural architecture critical for syntactic language. Therefore, these findings indicate that hominins at this site had already evolved left-hemispheric neural specialization linked to linguistic capability.

Which of the following, if true, most strongly supports the archaeologist's argument?

Geochemists analyzing vapor plumes venting from the fracture zones of an icy satellite observed elevated concentrations of molecular hydrogen and methane. Laboratory simulations establish that while hydrothermal serpentinization reactions produce abundant hydrogen, the abiotic reduction of dissolved carbon dioxide into methane proceeds far too slowly under the moon's inferred core temperatures to yield the observed methane concentrations. On this basis, the researchers conclude that biological methanogenesis by chemoautotrophic microorganisms in the sub-surface ocean is the primary source of the plume methane.

True or False: The finding that primordial methane trapped in sub-surface clathrate hydrates during the satellite's initial accretion would have completely decomposed and outgassed within the first billion years of the solar system's formation logically strengthens the researchers' conclusion.

Municipal Administrator: In an effort to curb residential water waste during peak summer drought conditions, the city of Oakvale installed automated smart flow-meters in every home across District 4. Simultaneously, District 4 households were transitioned to a tiered pricing structure that imposed sharply higher per-gallon rates for usage exceeding a basic threshold. Over the following year, residential water consumption in District 4 decreased by 18 percent, whereas consumption in neighboring District 5, which retained flat-rate pricing and standard mechanical meters, remained unchanged. Therefore, the implementation of tiered pricing was the primary cause of the reduction in water waste in District 4.

Which of the following, if true, most strengthens the municipal administrator's argument?

Match each of the following research arguments with the supplementary finding that most effectively strengthens its causal conclusion.

Historical Linguist: Dialect surveys across the Appalachian Mountain region reveal that grammatical features characteristic of seventeenth-century West Country English have persisted in isolated valley communities for generations. Anthropologists have traditionally attributed this linguistic preservation to extreme geographic isolation that prevented exposure to standard lowland dialects. However, recently uncovered municipal ledgers indicate that these valley settlements engaged in frequent, extensive commercial trade with major urban trading centers throughout the nineteenth century. Thus, the preservation of the traditional dialect was primarily driven by the community's active use of speech as a marker of shared social identity, rather than by an absence of linguistic exposure.

Which one of the following, if true, most strongly supports the historical linguist's argument?

Match each of the following arguments with the supplementary finding that most effectively strengthens its central conclusion.

Ecologist: Wild populations of the desert shrub *Larrea* produce volatile terpenes in their root zones. Although researchers once hypothesized that these subterranean terpenes primarily suppress the germination of competing plant species, recent field assays show that natural soil concentrations of the compounds are far too low to inhibit seed germination. However, *Larrea* specimens growing in soils with elevated terpene concentrations exhibit significantly less foliar tissue desiccation during prolonged droughts than do specimens in terpene-deficient soils. Given that terpene molecules are known to chemically bond with and thicken waxy cuticular layers on plant surfaces, the subterranean terpene vapor must rise into the canopy and directly reduce foliar water loss by reinforcing the leaves' cuticular wax.

Which of the following, if true, most strengthens the ecologist's argument?

Ecologist: Over the past decade, several metropolitan municipalities replaced standard high-pressure sodium streetlights with broad-spectrum white light-emitting diodes (LEDs). Following this transition, researchers documented a 45 percent drop in local nocturnal moth populations. The researchers concluded that the transition to broad-spectrum LEDs caused this decline, reasoning that the higher proportion of blue wavelengths emitted by white LEDs disrupts nocturnal insect navigation.

Statement: The finding that adjacent rural nature reserves retaining high-pressure sodium streetlights experienced stable moth populations over the same ten-year period strengthens the ecologist's argument.

Economist: To encourage retirement savings, several mid-sized firms replaced their opt-in retirement plans with an automatic enrollment system featuring a default employee contribution rate of 3 percent of gross salary. Five years after implementation, overall employee participation rose from 42 percent to 88 percent. Nonetheless, financial analysts argue that this policy change reduced the overall median retirement wealth accumulated by participating employees by retirement age. They reason that under the opt-in system, the self-selected participants chose an average contribution rate of 7 percent, whereas the vast majority of employees enrolled under the automatic system never actively adjusted their contribution rate above the 3 percent default.

Statement: The finding that workers enrolled under the automatic system are significantly less likely to open or contribute to supplementary individual retirement accounts than were workers under the opt-in system provides logical support for the financial analysts' conclusion.

Match each of the following research arguments with the supplementary finding that most strongly strengthens its conclusion.

Paleoclimatologist: Sediment core samples extracted from Lake Sylvan reveal a dramatic spike in charcoal microparticles around 850 CE, closely accompanied by a sharp decline in pollen from old-growth oak forests and an influx of pioneer scrub vegetation. Although many historians attribute this abrupt ecological transformation to widespread land-clearing by early agrarian migrants, it is more likely that a severe, multi-decade regional drought sparked extensive natural wildfires that reshaped the landscape.

Which of the following, if true, most strongly supports the paleoclimatologist's hypothesis?

Acoustic engineer: Open-plan emergency departments frequently experience high ambient noise levels, which have been suspected of contributing to cognitive fatigue and medication administration errors among triage nurses. To address this, a metropolitan hospital installed specialized sound-dampening acoustic baffles and absorbent wall panels throughout its emergency ward. Over the subsequent six months, the recorded rate of medication administration errors in that ward dropped by 35 percent. Thus, the physical reduction of ambient noise was directly responsible for the decrease in medication errors.

Which of the following, if true, most strengthens the acoustic engineer's argument?

Agronomist: Traditional drip irrigation systems deliver water directly to crop root zones at ground level, but in arid climates, substantial water is lost to surface evaporation during high-temperature periods. A newly designed sub-surface capillary system delivers water 15 centimeters beneath the soil surface. In a multi-year trial conducted in an arid valley, tomato fields utilizing the sub-surface system required 25 percent less water to produce the same crop yield as fields using traditional drip irrigation. Therefore, converting farms throughout the arid valley to the sub-surface system will substantially reduce the valley's overall agricultural water consumption. Which of the following, if true, most strengthens the agronomist's argument?

Match each logical argument with the supplementary finding that most strongly strengthens its conclusion.

Archaeologist: Smelting slag recovered from the Bronze Age coastal settlement of Karystos contains significant concentrations of manganese oxide. Because copper ore deposits at nearby Mount Oche naturally contain manganese, researchers have concluded that the copper smelted at Karystos came from Mount Oche rather than being imported from the Cycladic islands.

Which of the following, if true, most strengthens the researchers' argument?