22. My friend Mary is ___ 11-year-old beautiful girl and ___ girl everyone likes to work with.

A．a, a

B．a, the

C．an, a

D．an, the

总和电位来源于()

A．耳蜗毛细胞

B．血管纹细胞

C．听神经纤维

D．支持细胞

E．耳蜗核