串联试验可以提高（）
A.灵敏度
B.特异度
C.真实性
D.可靠性
E.收益
参考答案：B
— Is your father a doctor?
— Yes, he is. He _____ in Town Hospital. [ ]
A. has worked
B. is working
C. works
D. worked
与FeCl3反应呈阳性的化合物是( )
A．鞣质B．胆汁酸C．蛋白质D．洋地黄毒苷E．强心甾烯硫酸酯类
