Final Answer:
The theorist credited with proposing the psychosexual stages of development is Sigmund Freud (Option B).
Step-by-step explanation:
Sigmund Freud: Freud, an Austrian neurologist and the founder of psychoanalysis, introduced the concept of psychosexual development. According to his theory, individuals pass through a series of psychosexual stages during childhood, each characterized by a focus on different erogenous zones.
B.F. Skinner: B.F. Skinner was a behaviorist known for his work on operant conditioning, emphasizing observable behaviors and environmental influences.
Erik Erikson: Erik Erikson, a developmental psychologist, proposed the psychosocial stages of development, which focus on social and emotional development throughout the lifespan.
Jean Piaget: Jean Piaget, a Swiss psychologist, introduced the theory of cognitive development, emphasizing intellectual and cognitive growth in children.
Option B is the answer.