单项选择题

No sooner had they got in the wheat than it began to rain heavily.

A) 他们刚收割完小麦就开始下大雨了。
B) 他们还没收割完小麦,就下大雨了。
C) 他们在下大雨前,收割完了小麦。
D) 他们收割小麦前,就开始下大雨了。