PSAT Reading Question 3: Answer and Explanation

Question: 3

As used in line 30, "residual" most nearly means

• A. durable.
• B. remaining.
• C. steadfast.
• D. inhabiting.

Correct Answer: B

Explanation:

The question asks what the word residual means in line 30. Go back to the text, find the word residual, and highlight it. Carefully read the surrounding text to determine another word that would fit in its place, based on the context of the passage. This paragraph describes the electrospinning process, and lines 27–31 say that a fibrous jet is emitted from the cone and captured on a grounded collecting plate, however, any residual solvent in the ejected jet stream evaporates. Since residual refers to the solvent that evaporates, as opposed to what is captured on the collecting plate, it must mean something like "left over." Durable means "long-lasting," which does not match "left over," so eliminate (A). Remaining matches "left over," so keep (B). Neither steadfast nor inhabiting matches "left over," so eliminate (C) and (D). The correct answer is (B).