High-speed trains which travel through my home town up to 250 km per hour make it a small

问题补充：

High-speed trains which travel through my home town up to 250 km per hour make it a small world.

A. with

B. against

C. at

D. over

答案：

A. with

B. against

(答案→)C. at

D. over

解析：考查介词的用法。以什么样的速度，应用介词at,句意：穿过我们家乡旅游的高速列车以高达每小时250公里的速度行驶，使成为一个渺小的世界。故选C。