Who did you laugh at?
A
Who was laughing at you?
B
Who had been laughing at you?
C
Who laughed at you?
D
Who was laughed at by you?
Correct Answer: Who was laughed at by you?
Who laughed at you?Given sentence is in simple past tense and it is in active voice.
Rule :
Subject + (was/were) + V3 + Other agents
