Drill 6 · Reading & Writing · Hard Command of Evidence
SAT Reading & Writing: Hard Command of Evidence (Drill 6) is a Reading & Writing practice drill covering Hard Command of Evidence. It contains 5 original questions created by Brian Stewart, a Barron's test prep author with over 20 years of tutoring experience.
Five hard Command of Evidence questions spanning new findings, a line graph, a data table, and a scholarly quotation. Most wrong choices are accurate on their own but answer a slightly different question than the claim poses. Read each data display for the specific contrast the argument depends on.
After a drained wetland was restored along a creek's upper reaches, the creek's yearly peak flood height downstream dropped over the following years. Hydrologists proposed that the restored wetland itself lowers the floods by soaking up storm runoff and releasing it slowly. A skeptic suggested the floods might simply have seemed lower because the creek channel downstream had been widened and deepened over the same years, letting the same amount of water pass at a lower measured height.
Question 1. Which finding, if true, would most directly support the hydrologists' proposal?
Explanation: Choice D is the best answer because the proposal is that the wetland lowers floods by storing storm runoff, so the evidence must show the wetland actually holding water back. The wetland measured retaining a large volume of runoff during storms that would otherwise rush downstream directly demonstrates the storage mechanism the proposal names. Choice A is wrong because the towns the creek passes through are a side detail that does not connect the lower floods to the wetland's water storage. Choice B is wrong because a richer variety of nesting birds shows the habitat recovered but says nothing about flood storage. Choice C is wrong because a wider, deeper channel supports the skeptic's rival explanation for the lower measured height, not the wetland one.
A conservation group restored a drained wetland along the upper reaches of a creek in 2004, expecting the spongy wetland soils to absorb storm runoff and lower the creek's yearly peak flood height downstream. The group tracked the annual peak height on that creek and on a nearby creek with no wetland restored upstream of it. They concluded that the restoration, rather than a region-wide change in rainfall, lowered the floods, reasoning that a broad shift in weather would have moved both creeks together.
Question 2. Which choice best describes data from the graph that support the group's conclusion?
Explanation: Choice D is the best answer because the conclusion needs the restored creek to change only after the wetland work while the control does not, which separates the restoration from a region-wide weather shift. The graph shows the two creeks running together near three and a half meters until about 2004, after which the restored creek drops toward under two meters while the control holds level, exactly that timing. Choice A is wrong because the single lowest point in the final year is one endpoint and says nothing about whether the drop lines up with the 2004 restoration. Choice B is wrong because describing only the control creek's steadiness never compares it to the restored creek, so it cannot show the restoration had an effect. Choice C is wrong because the two creeks were close to equal before 2004 rather than the restored creek being lower every year, so this misreads the graph.
When two trading communities came into regular contact several centuries ago, one community's language absorbed a wave of new words from the other. In an essay, a student argues that these words were borrowed not for prestige or fashion but out of practical necessity: the speakers needed names for unfamiliar goods that arrived through the new trade and had no words of their own for them.
Question 3. Which quotation from a scholarly article best supports the student's argument?
Explanation: Choice B is the best answer because the argument is specifically that the words filled a practical gap, namely the lack of any native name for newly traded goods. The keyed quotation ties the borrowed terms directly to imported commodities the receiving language had no word for, which matches the claimed necessity. Choice A is wrong because that borrowing peaked when trade was heaviest shows the words came in with trade but not that they filled a naming gap rather than serving fashion. Choice C is wrong because native coinages later replacing the borrowings describes what happened afterward and does not establish why the words were taken in to begin with. Choice D is wrong because treating the foreign words as a mark of worldliness supports the prestige explanation the student is arguing against, not the practical-necessity one.
People who recover from a certain infection are usually protected against catching it again. Researchers found that recovered patients carry high levels of a particular antibody in their blood, and concluded that this antibody is what protects them, proposing that it neutralizes the germ before it can take hold. They based the conclusion on the antibody being abundant in protected people.
Question 4. Which finding, if true, would most directly weaken the researchers' conclusion?
Explanation: Choice C is the best answer because the conclusion is that this antibody provides the protection, so a finding that recovered patients with almost none of it resist reinfection just as strongly shows protection does not track the antibody, undercutting the proposed cause. Choice A is wrong because the antibody appearing in other infections does not address whether it is what protects against this one. Choice B is wrong because how long the antibody lingers after recovery says nothing about whether it is responsible for the protection. Choice D is wrong because the germ's size compared with other targets never tests whether this antibody is what blocks reinfection.
Carriers of a Recessive Trait Across Four Generations of a Bred Line
| Generation | Animals tested | Carriers found |
|---|---|---|
| 1 (founders) | 40 | 4 |
| 2 | 40 | 10 |
| 3 | 40 | 18 |
| 4 | 40 | 6 |
Because carriers were being bred without screening, breeders worried that the share of animals carrying a recessive trait might keep climbing each generation. The carrier count does rise from Generation 1 through Generation 3. The team was surprised that the pattern did not hold, noting that the most recent generation, Generation 4, instead ________
Question 5. Which choice most effectively uses data from the table to complete the statement?
Explanation: Choice B is the best answer because the surprise is that the newest generation breaks the rising trend. With 40 animals tested each time, carriers climb from 4 to 10 to 18 across the first three generations but fall to 6 in Generation 4, a sharply lower share than Generation 3's 18, so the carrier rate drops instead of continuing to rise. Choice A is wrong because this is true from the table, since 6 exceeds the founders' 4, but a comparison with the first generation misses the surprise, which is the drop from Generation 3. Choice C is wrong because this is also true, as 6 is far below the 28 carriers of Generations 2 and 3 together, yet that sum is not the comparison the team's surprise turns on, namely the fall from the generation just before. Choice D is wrong because every generation did test the same 40 animals, so this is accurate, but holding the sample size constant is exactly why the carrier count itself, not the number tested, is what fell.