amity = freindly relationship.
Mutability = being capable of mutation(changing of a structure of a gene).
others are quite self explanatory.
You can comfortably notice there is only one synonym pair and that' s also the only one that seems relevant.
So,while hitting at Sentence Equivalence
Read question Sentence.
Think of a word on your own,no need to worry here if you can't think of something.
Try to find a synonym pair most of the times