In which of the following cities are located 3 zonal headquarters of Indian Railways?

Guwahati
Mumbai
New Delhi
Kolkata

The correct answer is C. New Delhi.

New Delhi is the capital of India and the headquarters of the Indian Railways. It is also the location of the headquarters of three zonal railways: Northern Railway, Western Railway, and Central Railway.

Guwahati is the capital of Assam and the headquarters of Northeast Frontier Railway. Mumbai is the capital of Maharashtra and the headquarters of Western Railway. Kolkata is the capital of West Bengal and the headquarters of Eastern Railway.