UTG bets 15bb, BB folds

Multi-way River | 3-way: BTN | 100bb effective | Difficulty: Beginner

Players in hand: UTG, Hero (BTN), BB

Hero hand

A♣A♦

Board

K♥7♦4♠2♣9♥

Action so far:
Pot 24bb on river K♥7♦4♠2♣9♥
UTG bets 15bb, BB folds

Pot: 24bb   To call: 15bb

Villain range: KK,77,44,99,22,bluffs (AQ, AJ missed)

Your move: