Answer : 2. "आपदा प्रबंधन अधिनियम, 2005"
Explanation :

1. By the Disaster Management Act, 2005, the District Collector has been made the Chairman of the District Disaster Management Authority.

2. Disaster has been defined in the Disaster Management Act, 2005.

3. According to this Act, disaster means "devastation, accident and serious incident" caused by natural or man-made causes in any area.

4. Under the Disaster Management Act, 2005, the government has declared the Covid-19 pandemic a disaster.