

You are a specialist in playing 6-handed No Limit Texas Holdem. The following will be a game scenario and you need to make the optimal decision.

Here is a game summary:

The small blind is 0.5 chips and the big blind is 1 chips. Everyone started with 100 chips.
The player positions involved in this game are UTG, HJ, CO, BTN, SB, BB.
In this hand, your position is UTG, and your holding is [Six of Diamond and Six of Club].
Before the flop, UTG raise 2.0 chips, and BTN call. Assume that all other players that is not mentioned folded.
The flop comes Five Of Club, Two Of Diamond, and Three Of Heart, then UTG check, and BTN check.
The turn comes Ten Of Diamond, then UTG check, and BTN check.
The river comes Four Of Club, then UTG bet 3 chips, and BTN raise 10 chips.
You currently have Straight(Straight, Two to Six).

Now it is your turn to make a move.
To remind you, the current pot size is 18.0 chips, and your holding is [Six of Diamond and Six of Club]. You currently have Straight.

Decide on an action based on the strength of your hand on this board, your position, and actions before you. Do not explain your answer.
Your optimal action is: