How did the bracero program benefit both Mexican and Americans?

How did the bracero program benefit both Mexicans and Americans?

Explanation:

The Mexicans benefited from the bracero program because they were able to get a good living with food, water, and shelter. ... The U.S. government changed its policy toward Japanese Americans by letting Japanese Americans fight in the war.

answer; i believe the correct answer is (a) the correlation between the cause variable and outcome variable is zero;