Kojagiri Poornima is a festival celebrated primarily in _______ on the full moon day of Ashwin month.

The correct answer is Maharashtra.

Explanation:

1. About Kojagiri Poornima:
Kojagiri Poornima, also known as Sharad Purnima, is a harvest festival celebrated on the full moon day (Poornima) of the Hindu lunar month of Ashwin (which usually falls in September or October). It signifies the end of the monsoon season and the arrival of autumn.

2. Celebration and Significance:
In Maharashtra, the festival holds special cultural significance. It is traditionally believed that Goddess Lakshmi travels across the night sky asking "Ko Jagarti?" (meaning "Who is awake?"). Devotees stay awake at night, worshipping Goddess Lakshmi and the Moon god (Chandra Dev). A key tradition of Kojagiri Poornima is drinking sweetened milk infused with saffron, cardamom, and dry fruits (known as Kojagiri milk or Masala milk) after it has absorbed the light of the full moon.

3. Conclusion:
Hence, Kojagiri Poornima is celebrated primarily in Maharashtra among the given options.