

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 BTN, and your holding is [Ace of Spade and Four of Spade].
Before the flop, UTG raise 2.0 chips, BTN raise 7.5 chips, and UTG call. Assume that all other players that is not mentioned folded.
The flop comes Ten Of Heart, Four Of Club, and Five Of Diamond, then UTG check, and BTN check.
The turn comes King Of Diamond, then UTG check, BTN bet 18 chips, and UTG raise 36 chips.
You currently have One Pair(One Pair, Fours with Ace, King, Ten kickers).

Now it is your turn to make a move.
To remind you, the current pot size is 70.0 chips, and your holding is [Ace of Spade and Four of Spade]. You currently have One Pair.

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: