Mr. Smith I should tell you this is the fifth time you me for my twin sister.A. have mis

问题补充：

Mr. Smith, I should tell you this is the fifth time you me for my twin sister.

A. have mistaken

B. are mistaking

C. mistook

D. are mistaken

答案：

(答案→)A. have mistaken

B. are mistaking

C. mistook

D. are mistaken

解析：句意：史密斯先生，我应该告诉你这是你第五次把我误认为是我的孪生妹妹。根据前面的this is the fifth time可知，后面用现在完成时。故选A。