I hope that ______ that I’ve been able to do is of some use to you.

A．a few

B．the few

C．a little

D．the little

右下肺门外围影主要由哪些构成？（）

A、右下肺动脉和静脉

B、右下肺动、静脉和右中间段支气管

C、右下肺静脉

D、右下肺动脉、右下肺静脉、中间段支气管、淋巴结

E、右下肺动脉