Read the passage below. Then write the letter of the best answer to each question that follows. Monkey researchers have observed the process by which behavioral innovations spread from individual to individual and become part of a troop's culture independently of genetic transmission.^2 Consider the case of, a two-year-old female money. ^3 Imo and her troop of free-ranging monkeys live on the small Japanese island of Kashima, a high wooded mountain with a surrounding beach. In due course Imo began doing something that no other monkey had done. She would carry her sweet potatoes to freshwater pool, dip them in the water with one hand and brush the sand off with the other. 'Soon her companions began copying her. The behavior spread to the playmates' siblings and mothers. However, adult males, who rarely participated in the group's behavior, did not acquire the habit. "When the young females who engaged in potato-washing matured and had offspring of their own, all of the offspring learned to wash potatoes from their mothers. "Then Imo undertook another new behavior. She took the potatoes that she had in the fresh water and washed them anew in the sea. Imo apparently like the favor of the salt water. Within ten years, the practice of washing sweet potatoes in the sea had spread to two-thirds of the monkeys