The correct option is D All of the above
Health is a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity. The concept of health as a balance between a person and the environment, the unity of soul and mind can be achieved by many factors like balanced diet, personal hygiene, rest, exercise etc.
An individual can maintain his/her health by taking a routine and proper nutrition, a healthy lifestyle, clean drinking water, adopting domestic and personal hygiene, regular exercise etc.