The question requires identifying which union territory celebrates the Tarpa festival among the given options. The correct answer is Dadra and Nagar Haveli. Let's explore the reasoning:

Understanding the Festival: The Tarpa festival is a traditional celebration that primarily involves the indigenous communities of Dadra and Nagar Haveli, predominantly the Warli tribe. This festival is named after the Tarpa, a musical instrument made from bamboo, which plays a central role in the celebrations.

Reasoning for Correct Option:

• Dadra and Nagar Haveli: This region has a rich tribal heritage. The Warli tribe, residing in this union territory, is known for its vibrant culture, including the Tarpa dance and festival.

Elimination of Other Options:

• Ladakh: Celebrates festivals such as Losar, Hemis, and Galdan Namchot, primarily influenced by Tibetan traditions. The Tarpa festival is not part of this cultural spectrum.
• Andaman and Nicobar Islands: Known for festivals like Island Tourism Festival and others reflecting the diverse cultural influences of the settlers. Tarpa is not among these.
• Lakshadweep: Primarily celebrates festivals such as Eid and Milad-un-Nabi, reflective of the majority Muslim population and does not observe the Tarpa festival.

Thus, the Tarpa festival is indeed celebrated in Dadra and Nagar Haveli, reflecting the region's tribal cultural heritage, specifically that of the Warli tribe.

Conclusion: Dadra and Nagar Haveli is the correct union territory that celebrates the Tarpa festival owing to its significant tribal population, particularly the Warli community.