He climbed up a stationary wagon.

A. moving

B. speeding

C. shunting

D. standing

Answer: Option A

Solution(By Examveda Team)

Stationary : not moving or not intended to be moved.
Moving : in motion.
Speeding : move quickly.
Shunting : push or pull (a train or part of a train) from the main line to a siding or from one line of rails to another.
Standing : position, status, or reputation.

Antonym of Stationary is Moving