灌洗筒挂于床旁输液架上，其高度距床沿（）。

A.40~50cm处

B.50~60cm处

C.60～70cm处

D.70~80cm处

E.80~90cm处

Busy as they are, parents should________at least two hours every week to spend with their children.[ ]

A. set out  

B. set away

C. set aside  

D. set off