The teacher finds teaching little Tom ____ because he is too young.       [ ]

A. frustrating  

B. frustrated                

C. frustrate    

D. to frustrate

支配大腿内侧群肌肉的神经是（）

A.闭孔神经

B.坐骨神经

C.股神经

D.阴部神经

E.隐神经