Answer:
a. To encourage New York to ratify the Constitution.
Explanation:
The Federalist Papers were a series of 85 essays published in 1787 to explain and defend the Constitution that had been proposed at the Philadelphia Convention (1787) and to encourage New York, as well as other populous and strong states, to ratify it.
At the time it was decided that each state would hold a convention to debate and ratify or reject the Constitution and if it was ratified by 9 of the 13 states, then the Constitution would come into effect. Its ratification, however, was a slow process. Even though states like Delaware, Pennsylvania, New Jersey, Georgia, and Connecticut quickly ratified it, strong and populous states like Massachusetts, New York, and Virginia, initially refused to sign it. The Federalists Alexander Hamilton, James Madison, and John Jay, then, decided to write a series of essays to gain support for its ratification.