下列哪个药主要自肾小管分泌排泄
A．青霉素
B．利福平
C．四环素
D．异烟肼
E．链霉素
参考答案：A
William found it increasingly difficult to read，for his eyesight was beginning to ________.[ ]
A．disappear
B．fall
C．fail
D．damage
穿时
