请选择DCBA4X2p'}:b5W'`I was _______ the point of telephoning him when his letter arrived.7b:g6k3w6?4Q)l4y(?/v
A. in7b:g6k3w6?4Q)l4y(?/v
B.to7b:g6k3w6?4Q)l4y(?/v
C.at7b:g6k3w6?4Q)l4y(?/v
D.on7b:g6k3w6?4Q)l4y(?/v