If a psychologist is researching the relationship between conscientiousness and health, she is probably a ________ psychologist.

A) cognitive/learning
B) humanistic
C) trait
D) psychoanalytic

Conscientiousness is one of the five major personality traits in the trait theory of personality, which suggests that individual personalities are composed of broad dispositions. A psychologist studying the relationship between conscientiousness (a personality trait) and health is likely focusing on how these stable personality characteristics influence behavior and outcomes, which aligns with the interests of a trait psychologist.