The answer is:
b to convince readers that Britain has treated the colonists unfairly.
In the excerpt from the Declaration of Independence, the author mentions how Britain has has unjust methods. First, he acknowledges British "attempts by their legislature," usurpation, and the fact that the English government has has not listened to the colonies' claim for justice, even though Americans are their descendants.
The purpose of King’s letter is to cause negotiation to fight crisis.
