Correct Answer - Option 1 : Tranquil : Serene
The logic followed here is:
Sympathy is the synonyms of Affinity.
Similarly,
Tranquil is the synonyms of Serene.
And Vivid is the antonyms of Dark, Tame is the antonyms of Harsh and Vain is the antonyms of Modest.
Hence, "option 1" is the correct answer.