I'm choosing position 2,1 (middle of bottom row) because it serves two purposes: 1) It blocks a potential win for my opponent who has Xs at 2,0 and 2,2, and 2) It creates a potential winning opportunity for me in the middle column, as I can follow up with a move at 0,1 in my next turn to create a vertical line of Os at positions 0,1, 1,1 (which is blocked by X), and 2,1. Playing defensively to block the opponent's immediate win while setting up my own winning strategy is the optimal move here.