I didn't like any of the answer choices, but I comfortably eliminated D. I still fail to see how D is even remotely parallel to the stimulus. Additionally, what makes A incorrect? Isn't the general point of the argument that you shouldn't do things too quickly? Doesn't A do this? How does the reasoning in D capture this idea?
Comments
Species (X) can survive environmental change (Y), as long as it's not too rapid (/Z). Thus, the threat to survival (/X) is not because of change itself (Y), but because it is too rapid (Z IS occurring).
people (X) don't fear change (Y)/can survive change, as long as they are not uninformed (/Z). Thus, the reason why people are scared (/X) isn't because of change (Y), but because they are not informed (Z is occurring).