Option 1 - Andaman and Nicobar Islands:

Andaman and Nicobar Islands is a Union Territory of India and it is the correct answer to the question. It has more than fifty percent tribal population of the total population. The indigenous people of Andaman and Nicobar Islands are mainly classified as Scheduled Tribes. They have been living in the islands for thousands of years and have their own distinct cultures and traditions. The tribal population of the islands is higher compared to other regions of India, making it the State/UT with the highest tribal population in the country.

Option 2 - Dadra and Nagar Heveli:

Dadra and Nagar Heveli is a Union Territory of India, but it does not have more than fifty percent tribal population. It has a significant tribal population, but it is not the State/UT with the highest tribal population.

Option 3 - Himachal Pradesh:

Himachal Pradesh is a state in India, but it does not have more than fifty percent tribal population. It has a sizeable tribal population, but it is not the State/UT with the highest tribal population.

Option 4 - Pondicherry:

Pondicherry is a Union Territory of India, but it does not have more than fifty