Why was Henry David Thoreau put in jail, prompting him to write the essay “Civil Disobedience”? A. He became a Union traitor and swore allegiance to the South during the Civil War. B. He helped slaves escape from Southern plantations and find freedom in the North. C. He built a cottage on Ralph Waldo Emerson’s property to study self-discipline. D. He refused to pay a poll tax as a protest against the Mexican-American War.