Which of the following factors influence physical development?

Concept: Physical development refers to age-related changes in body size, structure, motor skills, and physiological maturation. Educational psychology treats it as a multiply-determined process, shaped jointly by an individual's genetic inheritance, the surrounding environment, and physical activity — not by any single cause acting alone.

Application: In this item, heredity supplies the genetic blueprint that sets the potential range for height, body type, and rate of maturation. Environment — nutrition, health care, socio-economic conditions, and surroundings — determines how much of that genetic potential is actually realised. Physical activity, such as sports and exercise, further strengthens muscles, bones, and motor coordination as the body grows. Because the question asks broadly which factor(s) influence physical development, and heredity, environment, and exercise are each independently recognised contributors, the option that names all three together captures the complete, accepted picture.

• Heredity alone: heredity supplies the genetic potential for height, body type, and rate of maturation, but genetic inheritance alone does not complete the picture — the surrounding environment and physical activity also shape how a child actually grows.

• Environment alone: environmental conditions — nutrition, health care, and surroundings — strongly influence how much of a child's growth potential is realised, but environment by itself does not account for the genetic and activity-related contributions to physical development.

• Sports and exercise alone: regular sports and exercise build muscular strength, bone density, and motor coordination, but physical activity alone does not explain growth that is also driven by inherited genetic potential and environmental conditions.

Cross-check: This matches the standard child-development framework used in teacher-eligibility preparation, which lists heredity, environment, and physical activity/nutrition together as the recognised determinants of physical growth — confirming that no single factor among these fully accounts for physical development on its own.