循行于口的经脉有（）
A.手足阳明经
B.足阳明经、足厥阴经、冲脉、任脉
C.足太阴经、足少阴经
D.足阳明经、足厥阴经
E.足三阴经
参考答案：A
Is this the reason ________ at the meeting for his carelessness in his work?[ ]
A．he explained
B．what he explained
C．how he explained
D．why he explained
如果割除幼鼠的胸腺，则此鼠的免疫状况是（）
A.有全部的细胞免疫能力
B.丧失一切免疫能力
C.有全部的体液免疫的能力
D.保留部分体液免疫的能力
