Definition: In this task, you're given a statement, and three sentences as choices. Your job is to determine which sentence clearly disagrees with the statement. Indicate your answer as '1', '2', or '3' corresponding to the choice number of the selected sentence.
Input: Statement: We do not know which staff group will be most effective. Choices:  1. We have determined which is the most effective group. 2. It is unsure which group will be best. 3. The groups all work at different speeds.

1