The use of water closet and septic tanks is preferred to the use of bucket and pit latrines because

The use of water closet and septic tanks is preferred to the use of bucket and pit latrines because contaminated faeces are completely kept away from flies. Water closets and septic tanks are designed in such a way that the human waste is channeled away from the house and stored in an underground chamber called a septic tank. The septic tank is designed to digest and decompose the waste and discharge water into the soil. This system ensures that the waste is completely kept away from flies and other insects, preventing the spread of diseases. Conversely, bucket and pit latrines are not completely sealed, and the waste can attract flies, which can spread disease. Therefore, the use of water closet and septic tanks is a more effective way to prevent the spread of disease.