Why was Madison particularly concerned about factions in The Federalist, No. 10

a. He believed that factions pursuing their self-interest would work against the broader public interest.
b. He worried that factions were too focused on the public good and that they neglected to take care of their own needs.
c. He worried that the Constitution did not provide enough opportunities for factions to be involved in politics.
d. He worried that the faction he belonged to would lose power if the Constitution was ratified.

Answer: a