—Are you ? —Yes I am.A. a musicianB. musiciansC. musicianD. A and B

问题补充：

—Are you ? —Yes, I am.

A. a musician

B. musicians

C. musician

D. A and B

答案：

(答案→)A. a musician

B. musicians

C. musician

D. A and B

解析：考查名词的用法。句意为：-----你是音乐家吗？----是的。Musician是可数名词，单数时前面必须用冠词修饰，结合答语，故选A。