问题：
[单选题] Text 4 As the nation experiences one of the worst flu seasons in years,thousands of Americans have already died from influenza,according to the U.S.Centers for Disease Control and Prevention.Though th
A、We have learned enough ofit.
B、lt's a kind of virus with the highest fatality rate.
C、It claimed more lives ofits victims for its severity.
D、The vaccine efficacy was not high enough to control it.
参考答案：
C、It claimed more lives ofits victims for its severity.
● 参考解析
