Ricketsrickets nd pellagra r due to vitamin difficecny. kwashiorkor is due to only protein difficecny. but marasmus is both proteins nd calories difficecny disease nd it is found in infants below one yr

The correct answer is option 'D' - Marasmus.

Explanation:
Marasmus is a severe form of malnutrition that occurs due to a deficiency of both proteins and calories in the diet. It typically affects infants and young children, particularly those below the age of one year. When breast milk, which is highly nutritious and provides essential proteins and calories, is replaced by less nutritive food, infants are at risk of developing marasmus.

1. Definition of Marasmus:
Marasmus is a form of severe protein-energy malnutrition characterized by inadequate intake of both proteins and calories. It leads to significant weight loss, muscle wasting, and stunted growth.

2. Importance of Breastfeeding:
Breast milk is considered the best source of nutrition for infants, providing all the necessary nutrients in the right proportions. It is rich in proteins, fats, carbohydrates, vitamins, and minerals, which are essential for the baby's growth and development.

3. Insufficient Nutrients in Less Nutritive Food:
When breast milk is replaced by less nutritive food, infants are deprived of the necessary proteins and calories required for their growth. Less nutritive food usually lacks the essential nutrients present in breast milk, leading to malnutrition.

4. Role of Proteins and Calories:
Proteins are crucial for the development and repair of body tissues, including muscles, organs, and immune cells. Without adequate protein intake, the body is unable to build and maintain these structures, leading to muscle wasting and weakened immune system.

Calories, on the other hand, provide energy for various metabolic processes in the body. Insufficient calorie intake results in a lack of energy, leading to weight loss, fatigue, and decreased activity levels.

5. Symptoms of Marasmus:
Infants suffering from marasmus typically exhibit the following symptoms:
- Severe weight loss and muscle wasting
- Growth retardation
- Weakness and lethargy
- Irritability and decreased activity
- Thin, wrinkled skin
- Dry and brittle hair
- Prolonged diarrhea
- Poor immune function, leading to increased susceptibility to infections

In conclusion, when breast milk is replaced by less nutritive food low in proteins and calories, infants below the age of one year are likely to suffer from marasmus. It is essential to promote and support breastfeeding to ensure the proper nutrition and healthy development of infants.