Command of Textual Evidence on the SAT Reading and Writing section asks a student to choose the quotation or finding that most directly supports, illustrates, or weakens a claim.
After a scholarly or scientific scenario, the student must pick the option that best backs a historian's argument, most clearly undercuts a lab hypothesis, or shows that paired examples really do what the writer claims. Questions typically ask which quotation from an article is strongest, or which finding, if true, would most support or weaken that claim.
Traps are related but off-target evidence and quotations that restate an idea without proving it. Answer choices are brief quotations or compact hypothetical results.
Sample questions
Pick an answer to see whether it is right — nothing is saved, and nothing needs an account.
Question 1Easier
Historian Amira Cole argues that the labels on early botanical specimens did more than identify plants: because collectors repeatedly revised the labels as classifications changed, the labels also preserve evidence of scientific disagreement over time.
Which quotation from Cole’s article most effectively illustrates the claim?
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Answer: C — “On some sheets, one species name is crossed out and replaced by another, while a later note disputes both identifications.”
The crossed-out, replaced, and disputed identifications directly show labels recording changing scientific judgments.
Question 2Mid
Conservation biologists hypothesize that a waxy coating made by bacterium B7 protects marsh-grass seeds from salt damage. In laboratory trials, seeds carrying B7 survived salt exposure more often than seeds without the bacterium.
Which finding, if true, would most directly weaken the biologists’ hypothesis?
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Answer: B — Removing the genes that produce B7’s waxy coating did not reduce the survival of B7-carrying seeds under salt exposure.
If disabling production of the waxy coating does not reduce salt survival, the coating is unlikely to be the cause of the protection.
Question 3Easier
A university radio station ran two limited series last year: Fault Lines, about predicting structural failure, and Synapse Hour, about how brains parse speech. Taken together, the series illustrate the breadth of scientific fields the station is willing to put on air.
Which finding, if true, would most directly support the underlined claim?
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Answer: A — Fault Lines episodes cited geology, metallurgy, and civil engineering, while Synapse Hour episodes drew on psychology, neurology, and linguistics.
Naming several distinct disciplines across the two series directly supports a claim about scientific breadth; experts from one discipline, shared production details, and concentrating on one research problem within each field do not.
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