A punctuation question with the same words in each choice tests how sentence parts fit together. Read both sides and find each subject and main verb: who or what each part is about, and what it does. Periods and semicolons separate full sentences; a comma can attach extra information that can't stand alone, while words needed to finish a sentence take no mark. Cross out the ending to test its job, because a pause doesn't tell you which mark is needed.
Hints
- Hint 1
Read through the year and find the main verb that tells what Carson did.
- Hint 2
Check the ending about the movement and public awareness: does it have a subject and main verb of its own? Cross it out to test whether it's needed to finish the sentence.
Step-by-step
Test the ending
Step 1Find the complete sentence
Look back from the blank: Biologist Rachel Carson published the book already has a main verb that tells what Carson did. Does a punctuation mark already introduce extra information? No, and reading through 1962 gives a complete sentence that says who published which book and when. The sentence is complete at the year, so our next check is whether the ending can stand alone too.
- Step 2
Test whether the ending stands alone
The words starting with sparking and continuing through leading to greater public awareness of pesticide use describe results of publishing the book. Can this ending stand alone? No, because it has no subject, the person or thing a sentence is about, and its words ending in -ing aren't main verbs on their own. The ending is a nonessential phrase, extra information the sentence could do without: cross it out, and Carson still published the book in 1962. It depends on that complete sentence to tell us what caused the movement and the greater public awareness.
- Step 3
Set off the added results
A nonessential phrase at the end is set off with a comma, so the results need a mark between the year and sparking. That comma separates the added results about the modern environmental movement and public awareness from the main sentence. The version 1962, sparking has that comma. Choice C.