The boundary dispute between the U. S. and Mexico was simple. The U. S. claimed that the Rio Grande River was the border, but Mexico insisted it was the

River

A Guadalupe

B Colorado

C Brazos

D Nueces

Also 15 points in

The answer is D, the Nueces River.

Explanation:

Conflict with Mexico began when the United States annexed Texas as a state in 1845. Mexico claimed that the new border between Texas and Mexico was the Nueces River, while the United States contested the border was the Rio Grande.

b

explanation: