[单选题]It was not until he had lost his health （ ） he got to know its value.
A
that
B
until
C
what
D
when
正确答案：A
题目解析
本题考查强调句的判断与使用。 去掉it was以及空缺处连词后，句意依然完整，故本句符合强调句结构：It is/was+(被强调部分)+that+句子剩余部分，被强调部分为时间状语“not until he had lost his health”，A选项符合题意。 句意：直到他失去了健康，他才开始明白它的价值。
