you are aware of the trick used in advertisements I don’t think you are eager to buy.A.

问题补充：

you are aware of the trick used in advertisements ,I don’t think you are eager to buy.

A. Whether

B. Until

C. Though

D. Once

答案：

A. Whether

B. Until

C. Though

(答案→)D. Once

解析：考查状语从句连词的选择。Whether 是否， until 直到， though 尽管 once一旦 ，

句意为一旦你意识到了广告中使用的伎俩，我认为你就不会急切地区买东西了。