Dr. Marsh’s research is mainly guided by the principles of functionalism.
Option B
Introspection means that investigation or inspection of one's own emotional and mental processes. By functionalism, we mean mental states are recognized by what they do preferably than by whatever they are formed of.
These words can easily be distinguished by the definition, components of things like perception, thinking, and consciousness are mainly related to functionalism. Contracts are mean what the mind does in producing different kinds of behavior. The things in which Dr. Marsh's research is guided by functionalism.