The correct answer is: no article.
Dussehra is a Hindu festival that celebrates the victory of good over evil. It is celebrated every year on the tenth day of the month of Ashvina (September-October). The festival is marked by a number of religious and cultural activities, including the burning of effigies of the demon Ravana.
The use of an article in front of a noun depends on the context. In the case of Dussehra, the noun is a proper noun, which is a noun that refers to a specific person, place, thing, or event. Proper nouns are always capitalized and do not take an article.
Here are some examples of proper nouns:
- The United States
- The Eiffel Tower
- The Mona Lisa
- Dussehra
As you can see, none of these nouns take an article.
I hope this helps!