Choose the correct preposition from the options given to complete the following sentence.

My niece is doing a Master's degree ____ Mumbai.

in

The correct answer is Option (4) → in

Around suggests a general location, not specific to a city.

At is used for specific points in time or locations like buildings. ("at the meeting," "at school"). While Mumbai is a city, "in" is more natural when referring to studying within a city.

On is used for surfaces or specific days/dates.