Answer:
Heredity: Heredity and genes certainly play an important role in the transmission of physical and social characteristics from parents to off-springs. Different characteristics of growth and development like intelligence, aptitudes, body structure, height, weight, color of hair and eyes are highly influenced by heredity.
Sex: Sex is a very important factor which influences human growth and development. There is lot of difference in growth and development between girls and boys. Physical growth of girls in teens is faster than boys. Overall the body structure and growth of girls are different from boys.
Socioeconomic: Socioeconomic factors definitely have some affect. It has been seen that the children from different socioeconomic levels vary in average body size at all ages. The upper level families being always more advanced. The most important reasons behind this are better nutrition, better facilities, regular meals, sleep, and exercise. Family size also influences growth rate as in big families with limited income sometimes have children that do not get the proper nutrition and hence the growth is affected.