---How old is your mother?

---She is ______years old. Today is her ______birthday.

A．fourteen；fortieth

B．fourty; forty

C．forty;fortieth

D．fortieth;forty

阿米巴接触性杀伤机制不包括()

A．变形、活动

B．粘附、吞噬

C．细胞毒作用

D．趋化

E．酶溶解