When we talk about race and identity, in the following answers, which one is not correct about racial identity?

A、Racial classifications and identity are usually associated with a person’s external physical traits. ;
B、Race is a social construct, it arises from historical attempts to categorize people into different groups.;
C、The concept of race is further deconstructed by centuries of genetic intermixing.;
D、Race can not be used to categorize people.