Answer:
C. through printed packets
Explanation:
The Federalists refers to a group of people who were keenly interested in the ratification of the federal constitution of the United States of America in 1787. They unanimously believed and agreed that the Articles of Confederation wasn't adequate or sufficient enough to enhance good governance and serve the needs of the United States of America and as such required a new government having greater powers at the national level.
Some of the notable members of the Federalists were Benjamin Franklin, George Washington etc.
The Federalists were a group of people who were well funded, organized and as a result made use of the printed media extensively.
Hence, the people learnt about the arguments posed by federalists through printed packets stating why the people should give approval or consent to the new constitution.