The correct answer is B) Athens helped other Greek city-states rebel against Persian rule.
The event that was a cause of the Persian War was "Athens helped other Greek city-states rebel against Persian rule."
Persia and Greece confronted each other in armed battles called the Persian Wars during the 5th century BCE. Historical battles that became legends in the history of these nations in ancient times were fought. Among them were Thermopylae, Marathon, Salamis, and Plataea. This last one represented the final battle where the Greeks definitively defeated the army of Xerxes, son of King Darius.
