Who among the following displays an influence of the Yakshagana folk tradition in his plays?

The correct option is Girish Karnad.

Explanation:
Girish Karnad (1938–2019) was one of India's most influential modern playwrights, film directors, and actors, primarily writing in the Kannada language. He was a key figure in the post-independence Indian theater movement, which sought to create a modern Indian drama by drawing inspiration from indigenous cultural roots, myths, history, and folk performance arts.

One of his most celebrated plays, Hayavadana (1971), directly incorporates conventions and techniques from Yakshagana, a traditional folk theater form of Karnataka. Yakshagana typically combines dance, music, song, scholarly dialogues, and colorful costumes to enact mythological stories. In Hayavadana, Karnad utilizes several elements of Yakshagana, such as:
1. The Bhagavata: The traditional narrator who comments on the action, interacts with characters, and guides the audience through the narrative.
2. The use of masks, half-curtains, and puppets.
3. The worship of Lord Ganesha at the beginning of the play (the Puja convention).
4. A blend of music and mime to represent abstract ideas and inner dilemmas.

By blending the traditional structure of Yakshagana with modern existential themes, Girish Karnad successfully created a unique idiom for contemporary Indian theater, making him the playwright most associated with this folk tradition among the given options.