The correct options are
A A disease-free person can be called healthy.
B The functioning of body organ(s) changes during a disease.
C Balanced diet maintains good health of an individual.
∙ The mere absence of any disease does not mean that the person is healthy. A person is called healthy if he or she is physically, mentally and socially fit.
∙ During any disease the function or appearance of one or more systems of the body changes. These changes give rise to various signs and symptoms of the disease.
∙ Balanced diet provides us with proteins, carbohydrates, fats and other nutrients in an adequate amounts.
∙ Good economic conditions are necessary to meet basic needs, such as healthy food and proper shelter and to obtain the means to maintain necessary hygiene and thus contribute to the maintainance of proper health.