Correct Response: A. To a large degree, an individual's body type and composition are determined by heredity, or genetics. Although environmental factors such as physical activity, nutrition, and disease influence the full expression of inherited traits, scientific studies confirm that genetics play a major role in determining body type and body composition (the proportion of fat, muscle, and bone in an individual's body). While certain predispositions related to stress and illness (B) and physical strength and flexibility (C) may be influenced by heredity, environmental conditions more significantly influence the development of these conditions than body type. In personal development, quality of relationships (D) are affected by many social and emotional factors, such as the presence of early positive relationships, secure attachments to caregivers, and nurturing environments.
