The river that forms the border between mexico and the us state of texas is the
a.
baja california
b.
amazon river
c.
rio grande
d.
colorado river

The correct answer is - C. Rio Grande.

The Rio Grande River is the biggest river in the southwestern part of the united States, as well as the northeastern part of Mexico. This river starts its flow in the highlands in Colorado, continuing towards New Mexico's and Texas's border and forming small portion of it. After that, the Rio Grande is actually forming the entire border between the United States's state Texas and Mexico, with the river moving in a roughly northwest-southeast direction. It ends its flow into the Gulf of Mexico.