Answer : 4. "बौद्ध दार्शनिक"
Explanation :

Nagarjuna (30 June 1911 – 5 November 1998) was an outstanding writer and poet of Hindi and Maithili. Nagarjuna, a connoisseur of many languages and a progressive minded litterateur, apart from Hindi, also wrote original works in Maithili, Sanskrit and Bengali and also did translation work from Sanskrit, Maithili and Bengali.