Explanation:

- The National Disaster Management Authority (NDMA) is the apex body in India for disaster management.

- The structure and leadership of NDMA are outlined by the Government of India to ensure effective disaster management.

Explanation of Options:

- Option 1, Prime Minister:

- The Prime Minister of India is the ex-officio Chairperson of the National Disaster Management Authority (NDMA).

- Option 2, Home Minister:

- The Home Minister of India assists in coordinating disaster response but is not the head of NDMA.

- Option 3, President:

- The President of India is the ceremonial head of state and does not head the NDMA.

- Option 4, Defense Minister:

- The Defense Minister is responsible for national defense and does not lead the NDMA.

- Option 5, Chief of Army:

- The Chief of Army Staff leads the Indian Army and is not involved in heading the NDMA.