Nature is at its most beautiful in spring ________ all kinds of flowers are in blossom, _______ attracts people from all walks of life to take a spring outing.

A．when; which

B．which; where

C．when; that

D．that; which

环孢素所致严重的不良反应是（）。

A.血尿酸和肌酐升高

B.呼吸窘迫综合征

C.肝坏死

D.深静脉血栓形成

E.骨质疏松症