What led to the end of the Mexican Revolution?

sporadic violence and clashes between federal troops and various rebel forces

Explanation:Many historians regard 1920 as the end of the revolution, but sporadic violence and clashes between federal troops and various rebel forces continued until the reformist president, Lázaro Cárdenas, took office in 1934 and institutionalized the reforms that were fought for during the revolution and were legitimized in ...

your answer would be (a)

b) race riots in several cities