You will be successful in the interview ____ you have confidence.

A．before

B．once

C．until

D．though

下呼吸道感染病原学诊断中，经支气管肺泡灌洗分离到病原菌数为（）

A.≥10²cfu/ml

B.≥10³cfu/ml

C.≥10⁴cfu/ml

D.≥10⁵cfu/ml

E.≥10⁶cfu/ml