Which among the following cities of India will have mid-day Sun exactly overhead only once a year?

The mid-day Sun is exactly overhead twice a year for locations situated between the Tropic of Cancer (23.5°N) and the Tropic of Capricorn (23.5°S) [2]. For locations situated exactly on the Tropics, the Sun is overhead only once a year during the respective solstice [2]. Locations beyond the Tropics, such as Delhi and Srinagar, never experience the Sun at the zenith [2]. Nagpur (approx. 21.1°N) and Kolkata (approx. 22.5°N) are both located south of the Tropic of Cancer but very close to it. While cities well within the torrid zone see the Sun overhead twice, the question asks for cities that experience it 'only once'. Technically, only cities exactly on the Tropic of Cancer (23.5°N) see it once [2]. However, among the given pairs, Nagpur and Kolkata are the only pair where both cities are within the tropical zone, whereas other pairs include cities like Delhi, Srinagar, and Darjeeling which are north of the Tropic of Cancer and never see the Sun overhead.

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 18: Latitudes and Longitudes > Latitudinal Heat Zones of The Earth > p. 242
2. [2] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 2: The Earth's Crust > THE ALTITUDE OF THE MIDDAY SUN > p. 7