A、<img src="http://img.wangxiao.cn/examfiles/imgcache/attached/image/20140605/20140605160829_6718.png" alt="" />

B、<img src="http://img.wangxiao.cn/examfiles/imgcache/attached/image/20140605/20140605160838_4381.png" alt="" />

C、<img src="http://img.wangxiao.cn/examfiles/imgcache/attached/image/20140605/20140605160848_3930.png" alt="" />

D、<img src="http://img.wangxiao.cn/examfiles/imgcache/attached/image/20140605/20140605160900_7078.png" alt="" />