What's hero's best line?

100NL - Full Ring

Hero is CO ($97.50) with
Villain is HJ ($123.50)

Pre-Flop
MP1 calls $1
MP2 calls $1
Villain calls $1
Hero calls $1
Button calls $1
SB calls .50
BB checks

Flop (7 Players, Pot = $7)


5 checks
Hero bets $4
4 calls

Turn (5 Players, Pot = $27)


3 checks
Villain bets $6
Hero ?