Are you on about the Tabletop Game Warhammer 40k here, or some spin-off video game like Dawn of War? Because the former ("proper" 40k) has more races: Dark Eldar, Daemons and Tyranids being the main ones. There's also the different Space Marine chapters as well. And don't forget the squats! ;)
You called the quiz WH 40k "races", but you should have called it factions. Because a race are the humans and the daemons, not marines or chaos. Plus, you forgot important ones like Tyrannies, Kroot, Dark Eldar and probably others..