Which of the following statements about the relationship of national identity and ethnic identity are correct:

A、Sometimes ethnic identity and national identity emerge at the same time and they combine into one, even it’s hard to distinguish them.;
B、The development paths of ethnic identity and national identity are different.;
C、The way one gains the identity of a county is to become its citizen. ;
D、 Ethnic identity is a kind of innate identity, which is related to one's family, ethnic cultural values and traditional concepts.