Peter couldn't concentrate____ what he was doing while his family were watching TV.     [ ]

A. on          

B. to          

C. in          

D. for

1岁半女孩，咳嗽4天，发热2天，气急1天。初步诊断支气管肺炎。确诊最主要的体征是（）

A.呼吸急促

B.肺部细湿啰音

C.口唇、甲床青紫

D.鼻翼扇动，张口呼吸

E.两肺叩诊浊音，呼吸音减低