— Hello could I speak to Mr. Smith?— Sorry wrong number. There isn’t Mr. Smith here. A.

问题补充：

— Hello, could I speak to Mr. Smith?— Sorry, wrong number. There isn’t Mr. Smith here.

A. 不填

B. a

C. the

D. one

答案：

A. 不填

(答案→)B. a

C. the

D. one

解析：此处用不定冠词表示“某一个”。