Which one of the following town/cities has not been developed as an administrative headquarters after Independence?

Jamshedpur

The correct answer is Option (1) → Jamshedpur

Jamshedpur is an industrial city located in the state of Jharkhand in India. It was established by the Tata Group and primarily serves as an industrial and business center rather than an administrative headquarters.

The other options, Chandigarh, Gandhinagar, and Dispur, have all been developed as administrative headquarters. Chandigarh serves as the capital of both Haryana and Punjab, Gandhinagar is the capital of the state of Gujarat, and Dispur is the capital of the state of Assam.