大全269

1.        During the Renaissance, scholars were uncertain as to the location of Troy, and by the eighteenth century many historians doubted that Troy had ever existed.

(A) doubted that Troy had ever existed

(B) doubt that Troy has ever existed

(C) were in doubt as to the existence of Troy

(D) were doubtful concerning Troy’s existence（A）

(E) had doubts about Troy’s ever existing

c为什么不对，我觉得很对称

                 罗嗦

                 这里明显要求一个谓语，double可作动词充当谓语，就不要用其名词形式表达一个谓语概念

                 该用动词的地方用动词，该用名词的地方用名词