What is the main idea of the article "The Columbian Exchange - A History of Disease, Food, and Ideas?

During the paleolithic, hominins grouped together in small societies such as bands, and subsisted by gathering  plants  and fishing, hunting or scavenging wild  animals. the paleolithic is characterized by the use of knapped stone tools, although at the time humans also used  wood  and bone tools.

Answer (d) a boy who is angry at his parent, slips into an alley to avoid his mother and runs into his father;