Which of the following statements are the definition of identity?
选项：

A:Identity refers to the individual's fundamental and continuous self, and is the main concept of a person as an individual.;
B:Identity is a process of establishing contact between an individual and another person or between an individual and another group.;
C:Identity is the self-definition as an independent and distinct individual, including behaviors, beliefs and attitudes.;
D:Identity is the reflective self-conception or self-image that derived from family, gender, cultural, ethnic group, and individual socialization processes.