I'm choosing column 2 because it accomplishes two important goals simultaneously. First, it gives me three O's in a vertical line (at positions 2,3, 2,4, and 2,5), creating a strong threat that could win me the game on my next turn. Second, it blocks my opponent's potential diagonal threat - they could have formed a diagonal line with X's at positions 2,3, 3,4, and 4,5 if I didn't block this position. By placing here, I'm both creating an offensive opportunity and preventing a dangerous setup by my opponent.