The shifting commas and semicolons in the choices indicate this question is testing sentence structure. As you read the text from the beginning, think "Have I just read a complete idea"? Complete ideas are independent clauses that need to be connected properly. Here, the first sentence introduces a decline in the U.S. textile industry. The clause preceding the blank, "The agreement was not . . . ," contains a subject, predicate verb, and a complete idea, so, it is an independent clause. The clause following the blank, "China . . . entered . . . ," is also a complete idea. Predict that the correct answer will contain one of the four ways to connect these clauses: a comma together with a FANBOYS conjunction, a semicolon alone, a period, or phrasing that makes the second clause dependent on the first.
Choices (A) and (B) both contain semicolons, but (C) and (D) can be eliminated since these choices create run-ons. To choose between (A) and (B), consider the logic of the text to determine if the contrast keyword "however" belongs to the first clause (A) or the second (B). Since the idea that China was another factor in the decline of the U.S. textile industry contrasts with the suggestion in the first clause that the agreement could have been the only cause, (A) is correct. The comma separates the independent clause from "however" and the semicolon connects the two independent clauses. Choice (B) contrasts China's effects on the U.S. textile industry with those of the trade agreement, which is not the logic of the sentence.
