An anthropologist publishes their book about their fieldwork in Morocco. The anthropologist interviewed many people in the field and publishes much of those raw interviews as part of the text in each chapter. Why is this a polyvocal approach?

a. There is no actual survey data in the book.
b. It uses selective accounts of the informants to tell the whole story.
c. The voices of the informants are used to describe the ethnographers personal perspective.
d. It includes many voices from the people interviewed.