The girl          is reading a book under the tree is my sister. [ ]

A. who        

B. whose      

C. which        

D. whom

咽后隙与咽旁隙之间相隔的结构是：（）

A．筋膜

B．咽上缩肌

C．翼内肌

D．茎突咽肌

E．疏松结缔组织