Explanation:

- The Rajkuli Bhuyian are a community from Orissa (now Odisha), traditionally known as Bhuyans.

- Historically, many Bhuyian groups have claimed descent from the Kshatriya varna, the warrior and ruler class.

- They have been associated with landholding, ruling local areas, and having martial traditions.

- In the traditional varna system:

- Brahmin (Option 1) are priests and scholars.

- Vaishya (Option 2) are traders and merchants.

- Shudra (Option 3) are service providers and laborers.

- Kshatriya (Option 4) are warriors and rulers.

- The Rajkuli Bhuyian's claim matches with Kshatriya status.

Option 4: Kshatriya is the correct answer.