It was hard not to start  laughing when she starte...

Câu hỏi: It was hard not to start  laughing when she started to sing  

A It was easy to keep a straight face when she started to sing

B  It was hard to keep a straight face when she started to sing

C Start  laughing was not hard when she started to sing

D It was not difficult to start  laughing when she started to sing