Mexican immigrants was the most minority group affected by massive migration of Midwestern farmer to the Southwest. The first option is correct.
Despite its lengthy presence in the United States, the Mexican American population remains predominantly in the Southwest. The 1990 decennial census revealed that approximately 83% of Mexican people are located in one of five Southwestern states (Arizona, California, Colorado,New Mexico, Texas), a ratio of Mexican immigrants that was almost identical to that of the earlier decade.