While Scanning the Shelves in a Library, You Notice a Book

While scanning the shelves in a library, you notice a book written in the 1920s. If you opened it up to look for the chapter on motivation, you would be most likely to find that psychologists

A) had not yet discovered the concept of motivation.
B) believed that most animal behavior is instinctually motivated, but that human behavior is not.
C) had compiled a list of 10,000 human instincts.
D) were focusing on the role of expectations in motivating behavior.