Option d is the correct answer. The ancient name Nilotpala for Mahanadi was stated in Vayu Puran. The word Mahanadi is a compound of the Sanskrit words Maha ("great") and Nadi ("river"). The river flows through the states of Chhattisgarh and Odisha and is one of the major rivers of peninsular India. It has many tributaries such as Seonath, Mand, Ib, Hasdeo, Kelo, Ong, parry, Jonk, and Telen. The river is also known for the Hirakud Dam, which was the first major multipurpose river valley project after India's independence in 1947.