He hardly works.

A. strenuously

B. scarcely

C. mostly

D. arduously

Answer: Option B

Solution(By Examveda Team)

Strenuously : in a way that requires great physical exertion.
Scarcely : only just; almost not.
Mostly : as regards the greater part or number.
Arduously : requiring great exertion.
Hardly : scarcely (used to qualify a statement by saying that it is true to an insignificant degree).

Synonym of Hardly is Scarcely