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: To reflect concerns about the inherent limitations in the number of studies supporting a causal association between long-term exposure and mortality, an Alternative benefit estimate was derived from the large number of time-series studies that have established a likely causal relationship between short-term measures of PM and daily mortality statistics. Choices:  1. The big number of time-series studies was used to create an Alternative benefit estimate. 2. When every study was checked, there were no concerns about inherent limitations that indicated an association between long-term exposure and mortality. 3. Because we have identified a solid link between PM and mortality, PM emissions should be reduced immediately.

2