Experts Claim That Most Ethnic Identities Are a "Social Construction

Experts claim that most ethnic identities are a "social construction." What does that mean?

A) That they grow out of social contacts with an ethnic group
B) That they are identities that ethnic groups have taken on rather than one based on some inherent characteristic that was independently established
C) That they were based on networks of friendship that people established over time
D) That they are based on postmodern deconstructionism
E) That they no longer have any validity in fact