The National Disaster Management Authority functions under the Union Ministry…

Concept

Under the Government of India (Allocation of Business) Rules, 1961, a statutory body is attached to the ministry that holds the subject that body was created to administer. In India, disaster management is treated as a civil-administration and internal-security subject rather than a sectoral or scientific one, so the national authority created for it sits with the ministry that runs internal administration and the relief machinery.

Applying it here

The National Disaster Management Authority (NDMA) is a statutory body constituted under the Disaster Management Act, 2005 and chaired by the Prime Minister. That Act is administered by the Ministry of Home Affairs, whose Disaster Management Division handles the administrative and budgetary matters of the NDMA, along with the National Institute of Disaster Management and the National Disaster Response Force. The Union Ministry the NDMA functions under is therefore Home Affairs.

Contrast with the other ministries

• Environment, Forest and Climate Change: forests and wildlife, pollution control, environmental clearances and climate-change policy.

• Water Resources (now a department of the Ministry of Jal Shakti): irrigation, river-basin and groundwater development, dam safety and inter-State river water disputes.

• Defence: the Armed Forces, defence production and defence research; the Services assist in an emergency only when requisitioned by the civil authority.

Answer: Home Affairs.