Which theory asserts humans are preformed at conception and grows only in size until birth?

• A. Behavioralist Theory
• B. Mechanistic Theory
• C. Preformationist Theory
• D. Organismic Theory

Answer: (C)

Developmental theories consider whether an organism is preformed from conception or develops gradually. The statement describes a fully formed miniature human existing at conception that just grows bigger until birth. This is the core idea of preformationist theory, which holds that the organism is already formed in miniature from the start and only increases in size. Behaviorist theory focuses on learning through environmental stimuli after birth, not prenatal form. Mechanistic theory explains development as driven by physical processes and forces acting on the organism. Organismic theory emphasizes growth as an integrated, internal maturation of the whole organism. So the best match is the preformationist view.