Final answer:
The grievance that directly correlates with the notion of 'unalienable rights' is option 2: 'The king refused to approve laws that supported natural rights.' This signifies that the king was violating the colonists' fundamental freedoms, hence provoking a grievance.
Step-by-step explanation:
The founding principle, 'unalienable rights,' refers to the fundamental rights granted to every individual, which cannot be taken away or violated. These include the right to life, liberty, and the pursuit of happiness. Evaluating each option, it is clear that option 2: 'The king refused to approve laws that supported natural rights' has the most direct relationship to the idea of 'unalienable rights.' If the king refused to approve laws supporting the natural or unalienable rights of the colonists, this would indeed be a grievance and a primary motivator towards seeking independence. An example can be found in the various grievances designated in the Declaration of Independence against King George III, most notably those centering around the king's repeated violations of the colonists' rights.
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