Which one among the following statements about a healthy diet is correct?

• A. Regular eating of high energy snacks between meals is healthy since it provide energy and vitamins in plenty.
• B. Fruits and vegetables make a good choice because their energy content is high.
• C. A balanced diet must contain plenty of fat and protein with little carbohydrates and fibre.
• D. An optimal quantity of fat, protein, carbohydrate with adequate amount of water and fibre makes a healthy diet