How have anthropologists attempted to explain the universality of the incest taboo, including rare instances where brother-sister marriage is broadly favored?

The book edition is Cultrual Anthropology (8th edition) by Barbara Miller

Relying solely on your text, respond to the topics for this writing assignment using your own words and examples. Design your responses as if you are explaining facts, concepts, and ideas to someone who is not familiar with the subject matter. Be sure to include creative examples wherever they may be appropriate. Also, be sure to provide a title for each of your essay responses.

This assignment requires you to write essays in response to all of the following:

Part 1 In your own words, differentiate two distinctive features of cultural anthropology, ethnocentrism and cultural relativism. Give examples.

Part 2 Provide a cross-cultural overview of balanced and unbalanced modes of exchange. Give examples.

Part 3 How have anthropologists attempted to explain the universality of the incest taboo, including rare instances where brother-sister marriage is broadly favored? Give examples.