Reading and Writing: Craft and Structure
SAT Question of the Day for October 17, 2026
Marine biologists studying deep-ocean hydrothermal vents have documented an ecosystem that flourishes in conditions once thought incompatible with life. The organisms thriving near these vents ______ the widely held assumption that sunlight is a prerequisite for complex biological communities.
Which choice completes the text with the most logical and precise word?
- A.undermineCorrect answer
- B.perpetuate
- C.fabricate
- D.chronicle
Explanation
The correct answer is "undermine." The passage describes organisms that flourish without sunlight, which challenges or weakens the assumption that sunlight is necessary. "Undermine" means to weaken or damage the foundation of something, fitting this context precisely. "Perpetuate" means to continue or maintain, which is the opposite of what these organisms do to the assumption. "Fabricate" means to invent or manufacture something false, which does not describe the organisms' relationship to the assumption. "Chronicle" means to record events in order, which does not convey the idea of challenging or weakening.
How to use this question
Try the question before you read the explanation: cover it, commit to an answer, and then compare your reasoning with the worked solution. If you missed it, note the step where your approach went wrong rather than only the correct letter, and look for that same step the next time you see a similar question.
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