Final answer:
The Sons of Liberty contributed to the cause of independence by rallying together, spreading propaganda against British oppression, and enforcing boycotts on British goods.
Step-by-step explanation:
The Sons of Liberty contributed to the cause of independence by rallying together and taking various actions to resist British rule in the American colonies. They were not a group of spies that supported English rule of the Colonies (a). They actively worked to make life harder for Tories, who were loyalists who supported British rule (b). They did not want to negotiate with England; rather, they were opposed to British rule and independence (c and d).
The Sons of Liberty played a significant role in spreading propaganda against British oppression through their access to public media, such as newspapers and pamphlets. They used print media to sway public opinion and garner support for the cause of independence. Their relentless propaganda campaign aimed at influencing the masses and garnering support for the revolution (Struggle of the Loyalists).
Additionally, the Sons of Liberty enforced boycotts on British goods to exert economic pressure on Britain. They threatened retaliation against anyone who bought imported goods or used stamped paper. By organizing and promoting boycotts, they contributed to the economic resistance against British rule.