ExplanationThe clue here is that Plath produced just two volumes. This phrase, in addition to the comparison to the number of volumes her husband produced, tells you that she did not produce many.
Remember that before the blank you have the trigger word not, so you need a word that means productive. Choices (A), (B), (C), and (D) are all adjectives that describe what Plath might or might not have been, but they do not fit the given clue. Choices (E) and (F) are correct because they are synonyms of productive.
Hence options E and F are correct!
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