The students in our class always exercise a lot.        homework, they finished it very quickly.      [ ]

A. To      

B. As for    

C. As          

D. Because

关于股静脉的描述，下述哪项是错误的（）。

A.伴股动脉上行

B.在腹股沟韧带深面延续为髂内静脉

C.收集下肢、腹前壁下部、外阴等处的静脉血

D.在腹股沟韧带下方位于股动脉内侧

E.可进行穿刺或插管操作