Evaluating Environmental Policy Arguments

In a recent analysis of environmental policies, experts suggested that implementing stricter regulations on automobile emissions will lead to a significant reduction in air pollution. They argue that as emissions decrease, the overall air quality will improve, benefiting public health. Critics of this approach claim that while reducing emissions is important, it will not address other major sources of pollution, such as industrial waste and agricultural runoff.

Based on this discussion, which of the following would be most important to evaluate the validity of the experts' argument?