初中英语. It 's ___for the pupils to do morning exercises every day to keep healthy .

问题描述:

初中英语. It 's ___for the pupils to do morning exercises every day to keep healthy .
A necessary B familiar C similar
请翻译句子和选项
并加以说明原因
谢谢

A 小学生每天做早操来保持健康是很有必要地.
It's +adj.+for sb. to do sth.
某人做某事是.的