But gradually,people realized that only through making educated choices about their personal lives and habits ____they b
问题描述：
But gradually,people realized that only through making educated choices about their personal lives and habits ____they begain to pretect thenselves
A could B may C must Dshould
这题选什么?理由?
答
could 表示能够 句中有几个单词错了吧?!应该是：begin to protect themselves.