The Wilmot Proviso:

A) Transformed the debate over the War with Mexico into a debate over the expansion of slavery
B) Led to the annexation of Texas by joint resolution of Congress
C) Increased Northern fears of the Slave Power
D) Caused Southerners to become outspoken opponents of the War with Mexico

The Wilmot Proviso was a proposed amendment to a spending bill during the Mexican-American War that would have banned slavery in any new territories acquired from Mexico. Its introduction transformed the debate over the War into a larger debate over the expansion of slavery and increased Northern fears of the Slave Power. It did not lead to the annexation of Texas or cause Southerners to become outspoken opponents of the War.