Final answer:
Raymond Cattell described personality variations using 16 factors or source traits. These form the basis of the 16PF questionnaire, with each factor scoring on a continuum. Such trait theories are central to personality psychology, with models like the Big Five also being prominent. The correct option is D.
Step-by-step explanation:
Raymond Cattell claimed that 16 source traits could describe all the differences amongst personalities. Although initially Cattell identified about 171 traits, he later narrowed these down to 16 factors or dimensions of personality which he used to develop the 16PF (Personality Factor) questionnaire.
These factors included qualities such as warmth, reasoning, and emotional stability, and each factor is scored on a continuum, showing different degrees of expression in an individual's personality. These dimensions help in understanding the complex nature of human behavior and are critical in the study of personality psychology.
Trait theorists believe that personality can be understood by identifying stable characteristics and behaviors. While Cattell proposed 16 personality factors, other models, such the Five Factor Model or the Big Five, focus on the five broad dimensions of personality, which are openness, conscientiousness, extroversion, agreeableness, and neuroticism, often remembered with the acronym OCEAN.
Understanding these traits and how they differ across individual personalities is essential for comprehending human behavior and for the practical application in fields ranging from psychology to business and education. Assessments based on these theories, like the 16PF and the Big Five, are used widely in personality studies.