What is the house cat's closest relative?

Answer 1

The domestic cat is in the Felis genus, which consists of six species of cat:
Domestic Cat (Felis catus)
Black-footed Cat (Felis nigripes)
Jungle Cat (Felis chaus)
Sand Cat (Felis margarita)
Wildcat (Felis silvestris)
Chinese Mountain Cat (Felis bieti).

Answer 2

There has been much debate over the origins of the domestic cat over the last century or so. It is most likely that the African wildcat (Felis silvestris lybica), is the ancestor of the modern domestic cat. This species is found mostly in the deserts of Israel, Saudi Arabia, and other Middle Eastern countries and is thought that some individuals started living in close proximity to humans around ten to twelve thousand years ago.

These formerly wild felines became household companions, and the same cat species appear to have accompanied human tribes as they gradually migrated and spread throughout the world.