The American Victory at San Juan Hill in Cuba Can

The American victory at San Juan Hill in Cuba can be credited mostly to

A) the surrender of the Spanish troops after merely token resistance.
B) four African American U.S.regiments that bore the brunt of the fighting.
C) Theodore Roosevelt's Rough Riders,whose cavalry charge overwhelmed the Spanish defenders.
D) Cuban guerrilla fighters who diverted the Spanish while the American attack was developing.