Professor Risa Reynolds in her class on race and ethnicity discussed a recent sit-in of African American students in the administration building. She had both white and African American students present their views on the sit-in to her class. She was engaging in:.

multiculturalism

Explanation:

Multiculturalism refers to the coexistence of various cultures, where diversity encompasses ethnic, social, or cultural communities and is reflected in traditional practices, cultural assumptions and values, thought patterns, and communicative types. American society represents one of the most diversified countries because of the existence of heterogeneous cultures. As per the question, Professor Reynolds discussion in her  class on race and ethnicity and involvement of both white and colored students reflects multiculturalism.

economic