Colonial Opposition to the Stamp Act

During the period leading up to the American Revolution, the British government implemented a variety of policies and acts that angered the colonists. One of these was the Stamp Act of 1765, which required that many printed materials in the colonies be produced on stamped paper produced in London, carrying an embossed revenue stamp. This law was met with widespread resistance and protests from the colonists, setting the stage for future conflicts between the colonies and Great Britain. What was the primary reason for the colonists' strong opposition to the Stamp Act?