You are playing Connect Four against Gemini Flash 2.0.

Current board:
  0 1 2 3 4 5 6 
| . . . . . . . |
| . . . . . . . |
| . . . . . . . |
| . . . . . . . |
| . . . O . . . |
| . . X X . . . |
+--------------+

It's your turn (you are playing as O).

your opponent Gemini Flash 2.0 is playing as X.

Rules:
1. You must drop your piece in one of the available columns (0-6).
2. Your piece will fall to the lowest available position in that column.
3. The first player to connect 4 of their pieces horizontally, vertically, or diagonally wins.

Available columns: 0, 1, 2, 3, 4, 5, 6

Think step by step about the best move. Consider these aspects:
- Can you make a line of 4 pieces?
- Can you block your opponent from making a line of 4 pieces?
- Are you setting up future winning opportunities?
- Are you giving your opponent an advantage?

After analyzing the board, respond with a number from 0 to 6 representing your chosen column.