I find the black to be something like not diverse / uniform.
So only ‘homogenized’ option feels right.
Please help me with this question.
First, the only pair in the answer choices are “compromised” and “endangered.”
Second, regarding the sentence logic, I see your point. By using time contrast with the appositive, without looking at the answer choices the blank could definitely refer to the opposite of “diverse.” However, in the answer choices there is no pairing with “homogenous” that would result in a sentence with similar meaning. Alternatively, the blank is supported (via “which”) by the subsequent clause (“overshadow the native flora”). As such, “compromised” and “endangered” are the best answers, because they are the only ones that match “overshadow.” You can even use “once a mosaic of diverse species” to infer that the original species are dying out, therefore being engangered/compromised.