Final answer:
The correct answer is option c. The secret group known for protesting British taxes and sometimes resorting to violence was the Sons of Liberty, not to be confused with the Founding Fathers, Loyalists, or the Continental Congress.
Step-by-step explanation:
The secret group that formed to protect the rights of colonists and was known to sometimes use violence in reaction to imposed taxes and British authority was c) The Sons of Liberty. This group consisted of patriots who took direct action against British-imposed legislation like the Stamp Act. They were instrumental in organizing resistance and spreading propaganda through newspapers and pamphlets, urging peaceful protest while also engaging in more radical, sometimes violent acts to voice their frustrations.
In contrast, the Founding Fathers were a broader group including signatories of the Declaration of Independence, and the Loyalists were those who remained loyal to the British Crown during the American Revolution. The Continental Congress refers to the assembly of elected representatives from the colonies that eventually declared independence from Britain in 1776.