What? Is it the first time that this ?
A. happened
B. has happened
C. had happened
D. happens
网友回答
A. happened
(答案→)B. has happened
C. had happened
D. happens
解析：本题的固定句式为：It/This is/was the序数词 time that从句，句意：是某人第几次做某事的时候了。如果前面是is，后面就使用现在完成时；如果前面是was，后面就是过去完成时。本句中使用了is说明后面使用现在完成时。句义：什么？这是第一次发生这样的事情？根据句义说明B正确。