Complete Food: Milk

Milk is considered a complete food due to its rich nutrient content and its ability to provide a wide range of essential nutrients required for growth, development, and overall health. It is a valuable source of several essential nutrients, making it an excellent dietary choice for people of all ages.

Macronutrients in Milk:
- Proteins: Milk contains high-quality proteins that are essential for the growth and repair of body tissues. These proteins provide the necessary amino acids required for various bodily functions.
- Carbohydrates: Milk contains lactose, a natural sugar that provides energy to the body. It is a source of easily digestible carbohydrates.
- Fats: Milk contains a variety of fats, including saturated fats, monounsaturated fats, and polyunsaturated fats. These fats provide energy and help in the absorption of fat-soluble vitamins.

Micronutrients in Milk:
- Calcium: Milk is an excellent source of calcium, which is essential for the development and maintenance of healthy bones and teeth.
- Vitamin D: Milk is often fortified with vitamin D, which helps the body absorb and utilize calcium effectively.
- Vitamin B12: Milk is a significant source of vitamin B12, which is essential for the production of red blood cells and maintaining a healthy nervous system.
- Vitamin A: Milk contains vitamin A in the form of retinol, which is vital for maintaining good vision, promoting growth, and supporting the immune system.
- Riboflavin: Milk is a rich source of riboflavin (vitamin B2), which is involved in energy production and the metabolism of fats, carbohydrates, and proteins.
- Potassium: Milk provides potassium, an electrolyte that helps maintain proper fluid balance and supports healthy heart function.

Benefits of Milk as a Complete Food:
- Growth and development: The combination of proteins, carbohydrates, fats, vitamins, and minerals in milk makes it an ideal food for growth and development in children and adolescents.
- Bone health: The calcium and vitamin D content in milk contribute to strong and healthy bones, reducing the risk of conditions like osteoporosis.
- Muscle recovery: The proteins in milk aid in muscle repair and recovery after physical activity.
- Hydration: Milk has a high water content, making it an effective source of hydration.
- Nutrient absorption: The presence of fats in milk helps in the absorption of fat-soluble vitamins, such as vitamins A, D, E, and K.

In conclusion, milk is considered a complete food due to its rich nutrient profile, including macronutrients like proteins, carbohydrates, and fats, as well as micronutrients like calcium, vitamin D, vitamin B12, and potassium. Its diverse range of nutrients makes it a valuable dietary choice for individuals of all ages, supporting growth, development, and overall health.

Answer is (A)-Milk