请选择DCBA:q)b6R'U*o/Q0@8]-b1\8Y You’d better_________ him a letter at once.;`.k4l5]:{)d1F
A. to write;`.k4l5]:{)d1F
B. write;`.k4l5]:{)d1F
C. writing;`.k4l5]:{)d1F
D. to writing;`.k4l5]:{)d1F