____ students should be given more free time is suggested by many experts and welcomed by kids in school.

A．What

B．Why

C．Whether

D．That

年金是指一定期间内每期相等金额的收付款项，按付款时点的不同分为普通年金和预付年金。普通年金是指在一定时期内每期（）等额收付的系列款项。

A．期初

B．期末

C．期中

D．期内