To improved health, it is necessary to follow some good and basic hygienic behaviour particularly hand-washing with soap after defecating and before eating or preparing food. Handwashing with soap can significantly reduce the incidence of diarrhea. Good hand-washing practices have shown to reduce the incidence of other diseases, notably pneumonia, trachoma, scabies, skin and eye infections and diarrhoea-related diseases like cholera and dysentery. Therefore, the correct answer is option A.