Mariano Vallejo supported providing more fair treatment to the Mexican Americans and the Native Americans.
Option A is the correct answer.
Mariano Vallejo was a politician and rancher in the year the 1840s and also acted as a leader in transforming California.
Mariano Vallejo was known for his military operations for protecting California from the dominators, Russians, and made a settlement with the government of Mexico. He also transformed the Alta California which was the province of Mexico into the state of California.
Therefore, fair treatment of the Mexican Americans and the Native Americans was provided by Mariano Vallejo.
Learn more about the Mexican Americans in the related link:
https://brainly.com/question/3119472
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