A、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/e631ad9d-d70f-4a14-be7e-db7280db7c32.png"title="ex_1397114745660_0.png" alt="ex_1397114745660_0.png"/>
B、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/bd25e191-3f0f-454c-ae51-a58ccd8ac8f4.png"title="ex_1397114778362_0.png" alt="ex_1397114778362_0.png"/>
C、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/fb9ca7b4-7f2d-42e8-8831-c7d09bfe0cd3.png"title="ex_1397114841734_0.png" alt="ex_1397114841734_0.png"/>
D、<IMG src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/staticQuestionImg/4bce097d-522b-416a-aad8-646b3ec78205.png"title="ex_1397114871777_0.png" alt="ex_1397114871777_0.png"/>