—You had better _____ food to the tigers.

—Sorry, I  _____ do it again.[ ]

A. throw; will,                          

B. don't throw; won't

C. not throw; won't                      

D. not to throw; will

进入青春期身体发育的最显著的特点（　　）

A．肺活量增大

B．身高突增

C．对异性产生依恋

D．脑容量迅速增加