COMPASSION :

Answer: Option A

Similarity : the state or fact of being similar.
Contrast :abnormality, oddity, dissimilarity, disproportion, irregularity.
Cruelty :cruel behaviour or attitudes.
Kindness :the quality of being friendly, generous, and considerate.
Compassion :sympathetic pity and concern for the sufferings or misfortunes of others.

Synonym of Compassion is Kindness.