D is the answer. The statement says the wine is sold in distinctive tall, black bottle. Answer D says purchasers will buy on the basis of the impression of the most obvious feature of the bottle which links back to tall, black bottle. The Gold label is not the obvious feature here. Therefore, D weakens Danville Winery's response.

Answer A kind of strengthen the Danville Winery's response.
Answer B can not weaken Danville Winery's response because DW's response is about the gold label.
Answer C is irrelevant to the question.
Answer E is irrelevant because we are talking about distinctive design here.