URGENT The Mexican-American War was sparked by a dispute over
A.
the location of the border between the two countries.
B.
the creation of trade barriers between the two countries.
C.
the amount of the tariff on Mexican goods.
D.
the number of troops on the Mexican border.

A. The location of the border between the two countries.

Explanation:

Due to the annexation of the Republic of Texas in 1848. A dispute over the border I. 1845. Mexico claimed Texas ended at the Nueces River while the U.S. claimed that the border began at the Rio Grande.

i guess so you did not explain the answer clearly so i can't