_________ the lecturer more clearly, I arrived early and chose a front seat.

A．Hear

B．Hearing

C．Heard

D．To hear

小儿，1岁，生后未接种卡介苗，平素体弱。近1月咳嗽，食欲不振，午后微热，体温：37.8℃，肺部听诊呼吸音粗，无水泡音，为确诊应首选哪种检查

A．全血常规
B．肺部CT
C．血沉
D．血清病毒抗体测定
E．结核菌素试验