hypothetical flush on the board

[Guruman]

here you are in a B&M 4/8 or 5/10 game. Assume that on the river there is a flush on the board that your hole cards have no part of - so you play the board. small pot as everyone has show passiveness to this point. 3 players still in the hand and you are last to act.

a)Bet, call, call, hero?
b)bet, raise, call, hero?
c)check, check, bet, hero?

do your lines change with a larger pot?
thx!