PSAT Writing and Language Question 277: Answer and Explanation

Question: 277

• A. NO CHANGE
• B. process—an extensive climate-control system—will
• C. process, an extensive climate-control system—will
• D. process; an extensive climate-control system; will

Correct Answer: B

Explanation:

Difficulty: Medium

Getting to the Answer: The phrase "an extensive climate-control system" is parenthetical to the meaning of the sentence. Although it provides clarifying information about what "the measure" is, the sentence would still be logical even if the phrase were removed. Parenthetical information must be set off by a pair of matching punctuation marks, such as commas or dashes, so (B) is correct. (A) and (C) are incorrect because they include mismatched punctuation marks around the phrase. (D) is incorrect because semicolons cannot be used to set off parenthetical information.