not until

  选 B

参考；

I did not find my wallet until I got to the station 。 到了车站我才发现我的钱包不见了

如果表示强调，将not until提前，主句倒装

Not until I got to the station did I find my wallet lost 。

在肯定句中， till/until 意为“直到……为止”，主句的谓语动词须为延续性动词。

在否定句中， till / until 与否定词搭配，意为“直到……才”。

如果把“ not … until ”变成“ not until …”置于句首时，主句要倒装。

  例如：

　　　Go straight on until / till you comes to the post office。

　　　I won”t go away until you promise to help me。

　　　Not until he called me up did I know it。

　　　注意：若把 not until 引导的部分作为强调句型中的被强调部分，则主句中的主谓不倒装。例如：

　　　It was not until he took off his dark glasses that I recognized him。

   = Not until he took

"It was ... that..."固定用法,强调,排除A,C

"主语+not...until"所以排除D

综上所述,选B