He smiled at me _____ my help, saying nothing at that moment.[ ]

A. in respond to

B. in response to

C. responded to

D. responding

针对EDGE业务，MCS4编码方式的每PDCH理论流量为（）kbit/s。

A.15.6

B.17.6

C.20.2

D.22.4

E.29.6/27.2