When the H1N1 virus at first in Mexico, no one had the least idea that it would spread so rapidly throughout the world.
A. broke off
B. broke down
C. broke out
D. broke away
网友回答
A. broke off
B. broke down
(答案→)C. broke out
D. broke away
解析：考查短语辨析。句意“当H1N1病毒最初在墨西哥暴发时，没有人会想到它会传播得这么快。”A“折断，突然停止；解除”；B“分解，坏掉”；C“暴发”；D“脱离，打破”。故选C。