She was surprised __________ me last night. [ ]
A. to see
B. see
C. saw
答案：A
点估计是用样本统计量的（）来近似相应的总体参数。
A.实现值
B.估计值
C.近似值
D.精确值
下列物质中免疫原性最强的是( )
A．核酸B．蛋白质C．多糖D．半抗原E．脂类
