Hi All,
When a sentence includes an "intervening phrase", as this SC does, you should be able to "pull out" that intervening phrase and still have a complete, grammatically-accurate sentence. The first sentence in my post serves as an example. The phrase "....,as this SC does,...." is the intervening phrase. Pull it out and you still have a complete sentence.
Here, the intervening phrase begins with ", due to a decline in public....." and ends with the next comma. If we pull out that phrase, we're left with....
"During the first nine months of 1979, textbook publishers incurred substantial costs for creating products that....." We need an answer that grammatically completes this sentence. Since "products" is plural, we need a plural verb - in this case "were." Eliminate B and C.
Since the subject ("products") is clearly defined, we don't need another reference to it (so there's no need to include the word "products" again and there's no need for a pronoun). Eliminate D and E.
Final Answer:
GMAT assassins aren't born, they're made,
Rich
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