Help with May-FLEX LR Q24

It's a weakening question. I don't understand why answer is D.

Answer choice is saying the ordinary crop doesn't contain drug. But according to stimulus, after pollination, the ordinary crop may produce drug-producing crop, therefore drug may end up in food supply. Answer choice D doesn't weaken this argument.

I was indecisive between E and B. But I couldn't think of an explanation of D is the right answer. HELPP~