Italian Americans and Irish Americans began thinking of themselves as "whites" after three or four generations in the United States.That is because:

A) over time they achieved approximate equality with members of the majority group
B) they maintained their separate ethnic identity and over time became accepted by the majority group
C) they totally abandoned any sense,symbolic or otherwise,of their ethnic identity
D) they refused to marry individuals outside of their group
E) all of these choices

Italian Americans and Irish Americans faced discrimination and prejudice when they first arrived in the United States. However, they gradually gained economic and social mobility, leading to their assimilation into the broader American population. As a result, they began to think of themselves as "whites" over time, achieving approximate equality with members of the majority group. They did not abandon their ethnic identity entirely or refuse to marry outside of their group, but rather, they integrated into American society while also maintaining aspects of their cultural heritage.