The sight moved him to pity and compunction.

Answer: Option C

Confusion : uncertainty about what is happening, intended, or required.
Wonder : a feeling of amazement and admiration, caused by something beautiful, remarkable, or unfamiliar.
Regret : feel sad, repentant, or disappointed over (something that one has done or failed to do).
Anger : a strong feeling of annoyance, displeasure, or hostility.
Compunction : a feeling of guilt or moral scruple that prevents or follows the doing of something bad.

Synonym of Compunction is Regret