**Core Concept**
Protein energy malnutrition (PEM) in children less than 3 years is a complex issue that requires a multifaceted approach for effective management. The condition is characterized by a combination of inadequate protein and energy intake, leading to impaired growth and development.

**Why the Correct Answer is Right**
The correct answer involves addressing two critical aspects of PEM management: treating anaemia and pneumonia. Anaemia, often caused by iron deficiency, can exacerbate the effects of PEM, making it essential to treat this condition simultaneously. Pneumonia, a common infection in young children, can further compromise their nutritional status and overall health. By treating anaemia and pneumonia, healthcare providers can help alleviate the symptoms of PEM and create a more conducive environment for recovery. This approach is in line with the World Health Organization's recommendations for managing PEM in children.

**Why Each Wrong Option is Incorrect**
**Option A:** Supplying subsidised food from ration shops may not be sufficient to overcome PEM, as it may not provide the necessary protein and energy requirements for young children. Moreover, relying solely on subsidised food may not address the underlying causes of malnutrition.

**Option B:** Early supplementation of solids in infants is crucial for their growth and development, but it is not the most important factor in overcoming PEM. While solid foods can provide essential nutrients, they may not be sufficient to address the underlying nutritional deficiencies that lead to PEM.

**Option C:** Immunisation is essential for preventing infectious diseases, but it does not directly address the nutritional aspects of PEM. While immunisation can help reduce the incidence of pneumonia and other infections, it does not provide the necessary nutrients for growth and development.

**Clinical Pearl / High-Yield Fact**
In children with PEM, treating anaemia and pneumonia can significantly improve their nutritional status and overall health. This approach is often referred to as the "treat the treatable" strategy, which involves addressing the underlying causes of malnutrition to create a more conducive environment for recovery.

**✓ Correct Answer: D. bc. Treatment of anaemia and pneumonia in infant and toddlers.**