Why Is Race More Controversial as a Descriptor Than Ethnicity

Why is race more controversial as a descriptor than ethnicity or nationality?

A) Race is a new, untested concept for the scientific community.
B) Race cannot be chosen, whereas ethnicity and nationality can.
C) Race is highly visible, whereas ethnicity and nationality are more nuanced.
D) Race is highly fluid, whereas ethnicity and nationality are more static.
E) Race has little scientific basis, whereas ethnicity or nationality are objectively grounded.