‘NEERI’ is located at

The correct answer is A) Nagpur. NEERI, the National Environmental Engineering Research Institute, is a CSIR laboratory headquartered in Nagpur. It began in 1958 as the Central Public Health Engineering Research Institute and took its present name in 1974.

Why the others fail:

• Mumbai: Not the headquarters. Mumbai hosts a regional unit of CSIR and other institutes, but NEERI's seat is in Nagpur.
• Chennai: Home to several national labs and regional offices, but not NEERI's headquarters.
• Bengaluru: Houses major research bodies such as IISc and several CSIR labs, but NEERI is not based there.

The core concept is recognising national research institutions by their headquarters, which is a standard Prelims recall item. For Mains, NEERI's work on water treatment, waste management and pollution control ties directly to GS-III questions on environmental governance and sustainable development.

Trap: Candidates often guess a metro city for a national institute. Map major CSIR and DRDO labs to their actual cities, not to the largest city nearby.