Based on anthropological research with traditional cultures and cross-species research with chimpanzees, what can we say about how our ancestors breastfed for much of human history?

a Feedings were less frequent and, overall, children were exclusively breastfed for only a few weeks.
b. Feedings were less frequent, but, overall, children were breastfed for several years.
c. Feedings were more frequent, but, overall, children were exclusively breastfed for only a few weeks.
d. Feedings were more frequent and, overall, children were breastfed for several years.

Answer: D