The correct answer is - racial discrimination.
The racial discrimination, more often referred to as racism, is a discrimination type based on the physical appearance of someone, mostly the skin color.
The racism has its roots way back in the past, and it is only very recently when it was actually put under law control and it is forbidden. Even though there's big fines for racial discrimination, and more and more people are leaving it in the past, there's still groups and organization that promote it.
Simplified, the racism is any discrimination from a person/group/organization towards another person/group/organization based on race, and it can be a Caucasoid, Negroid, Mongoloid, that is the discriminator or the discriminated.
