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: Across-study variation can result from two possible causes. Choices:  1. The study deviation comes from one cause. 2. The study variation comes from two possible causes at any one time. 3. It can result from two likely causes.

1