Final answer:
Option C is an example of an inductive approach to studying personality, as it starts with observations and builds towards a general theory. It is related to the concept of extroversion and introversion, core to current personality models.
Step-by-step explanation:
An inductive approach to the study of personality involves making observations and then developing theories based on those observations. Option C, "After observing people at a party, you decide that extroverts enjoy parties more than introverts do," is an example of an inductive approach because it is based on specific observations that lead to a general conclusion about personality traits and enjoyment of social situations.
Sigmund Freud's method of developing his theory through in-depth interviews is referred to as a case study, which is a research approach that can provide detailed information about individuals but may have limited generalizability. Carl Jung introduced concepts of extroversion and introversion, which are central to current models of personality.