Final answer:
The correct answer is option the correct answer is: a. Advance from Corpus Christi to the Rio Grande.
Step-by-step explanation:
In January 1846, President James K. Polk gave orders to General Zachary Taylor and Commodore David Conner that would ultimately provoke the Mexican-American War. Polk directed Taylor to move his troops into the disputed territory between the Nueces River and the Rio Grande, an area claimed by both the United States and Mexico. This military maneuver was intended to assert U.S. claims over this territory.
Following Polk's instructions, when General Taylor's troops encountered a Mexican cavalry unit, a skirmish ensued, resulting in the deaths and injuries of U.S. soldiers. President Polk used this incident to declare that Mexico had "shed American blood upon American soil," which led to a U.S. declaration of war. Polk's action was based on the U.S. claim that the Rio Grande was the rightful border, contrary to Mexico's assertion that the Nueces River marked the boundary.