Greenwald and his colleagues (2003) asked both black and white participants to press a "shoot" button when the target appeared to be holding a gun (rather than a harmless object such as a flashlight). their results showed that all participants mistakenly shot at more targets who were black. the results showed that

I believe the answer is: Black.
This research indicates that the existence of racial bias that exist within people's unconscious mind.
This bias is proven to be influencing our judgement and action toward people outside our own race, and this would indirectly contribute to the hostile tension that exist between different races in society.