Until the driver orders her to give her seat to a white passenger.

The woman utters a single word that ignites one of the most important civil rights protests of the twentieth century, one word that helps America find its better self.

The word is “No.”

The driver threatens to have her arrested.

“You may do that,” says Rosa Parks.

A police officer arrives. He asks Parks why she won’t move.

“Why do you all push us around?” she answers simply.

“I don’t know,” he says. “But the law is the law, and you’re under arrest.”