The incident affected him so much that he could not forget it for several days.

A. upset

B. changed

C. influenced

D. controlled

Answer: Option C

Solution(By Examveda Team)

Upset : make (someone) unhappy, disappointed, or worried.
Changed : make or become different.
Influenced : have an influence on.
Controlled : not showing emotion; having one's feelings under control.
Affected : influenced or touched by an external factor.

Synonym of Affected is Influenced