Which statement about Cesar Chavez actions in support of farmworkers in California is true?
A. He persuaded farmers in other states to increase production to drive California growers out of business.
B. He urged striking Grape pickers to destroy crops in the field before they could be harvested.
C. He encourage migrants to move back to Mexico where they would receive higher wages.
D. He called for a strike and a boycott against grape growers who refused to allow unionized workers.