Official Explanation :

Split #1: active language. This is not definitive, but we suspect that the verb "to oppose" will be preferred over both nouns, "opponent" and "opposition". Choosing the verb form of a word makes a sentence more active.

Split #2: in (B), "an opponent of revolution with religious grounds" is an incorrect idiom. The correct idiom would be "on religious grounds". (B) is wrong.

Split #3: The idioms in (D) & (E), "it is known" or "as is known," suggest something that is common knowledge now. This changes the meaning. The modifiers "known to do X" or "known as Y" suggest that the person was famous in his time for these, but understandably, such things would only be known now to folks familiar with that historical period. Choice (D) & (E) change the meaning and are wrong.

Split #3: (D) also contains a logic error: it changes the meaning. The construction "opposed evolution religiously " comments on the quality of his devotion to his opposition, not the reasons for the opposition, which is the meaning of the prompt sentence. (D) is wrong for this reason as well.

Split #4: Concision. Choices (A) & (C) are all grammatically correct, but whereas (C) is wordy and awkward and indirect, (A) is sleek and elegant and powerful. (A) is the best answer.
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My Notes:
Reading comprehension