Mr. White who comes from_______ European country, has formed the habit of attending _______ church on Sundays.

A．an, the

B．an, /

C．a, /

D．a, a

气道激光手术最大的危险是（）

A.气胸

B.着火

C.激光误击穿气管导管套囊

D.非靶组织损伤

E.眼部损伤