The hill ____ is covered with trees is called Mang Hill. [ ]

A. of which top

B. whose the top

C. whose top

D. top which

鱼类急性毒性试验开始时，从驯养鱼中随机取出鱼并迅速放入各试验容器中，同一试验的所有试验用鱼应在（）min内分组完毕。

A.15

B.30

C.45

D.60