Danny is examining U. S. culture for the possibility that different immigrant communities in the United States maintain more or less separate cultures but might still manage to participate equally in economic and political life. His study focuses on which concept?

multiculturalism

Explanation:

Based on the information provided within the question it can be said that in this scenario Danny's study focuses on the concept of multiculturalism. This concept focuses on how society deals with cultural diversity in both a national and community level. Such as observing how different cultures living near each other live in a harmonious coexistence.