Explanation

Creating a filter: In this question, the original sentence is brief and possibly error-free, so we can move on to choice (B).

Finding objective defects: choice (B) distorts the intended meaning of the sentence. The fact that bonobos do not discriminate means they mate quite freely, so (B) has that part backwards. Choice (C) looks quite similar to (A); we can skip it for now. In (D), the phrase "so that" indicates that they do not form relationships in order not to discriminate. More properly, the first part of the statement and the second are similar, almost equivalent facts; the second one is an elaboration, not an outcome. So (D) is out. Choice (E) introduces a pronoun without reference, "it," so it's out. Deciding between (C) and (A) will really depend on the intended meaning of the sentence. Choice (C) presents the two clauses as separate, equal facts, since they are both independent clauses. Choice (A) presents them more as two aspects of the same idea, and that's truer to the meaning of the sentence. The correct answer is (A).