— _________________?

— Because it's warm. [ ]

A. Why do the flowers bloom in spring

B. Why do you put on your coat

C. Why do the leaves drop off the tree

气虚患者，复感外邪，应采用的治疗原则是（）。

A.治其标

B.治其本

C.标本兼治

D.先治标后治本

E.先治本后治标