The train leaves at 6:00 p.m.So I have to be at the ......

问题描述:

The train leaves at 6:00 p.m.So I have to be at the ......
The train leaves at 6:00 p.m.So I have to be at the station_____5:40 P.m.at the latest.
A:until B:after C:by D:around
为什么?

by有不迟于的意思