给白喉病人的易感接触者先后注射白喉抗毒素、白喉类毒素，这种免

搜题请搜索小程序“爱下问搜题”

问题单项选择题

给白喉病人的易感接触者先后注射白喉抗毒素、白喉类毒素，这种免疫为（）。

A．自然主动免疫

B．自然被动免疫

C．人工主动免疫

D．人工被动免疫

E．人工被动主动免疫

答案

参考答案：E

选择题

--- Are you Kate? ---

A．Yes, I’m.

B．Yes, I am.

C．I am.

D．No, I am.

单项选择题

Annie Jump Cannon, ________ discovered so many stars that she was called "the census taker of the sky".

A．a leading astronomer,

B．who, as a leading astronomer,

C．was a leading astronomer,

D．a leading astronomer who