When was the Wilmot Proviso first brought up in Congress?

A. Just after the war started

B. After the US forced the surrender of Mexican
troops

C. After the Treaty of Guadalupe Hidalgo was
signed

A. Just after the war started

Explanation:

This proviso was meant to resolve the Mexican-American war and it was proposed like three months into the what would be a two year war (thus it was brought up just after the war started)