Which of the following is not a faction in Tom Clancy's The Division?

The answer is CDC because the Centers for Disease Control and Prevention (CDC) is not a faction in Tom Clancy's The Division. The game is set in a post-apocalyptic version of New York City where various factions have emerged, each with their own agendas and conflicts. However, the CDC, which is a real-life organization focused on disease control, does not play a role as a distinct faction in the game's narrative.