The correct answer is Rapti.Rapti river originates in our neighboring country Nepal.Rapti River denotes one of the two ‚¬œ East Rapti River or West Rapti River.East Rapti River: It is a small river draining the Chitwan Valley in Nepal.Flowing from east to west, it forms the northern border of the Chitwan National Park, also joining the Narayani River inside the protected area.It flows through the Mahabharat Range.The tributaries: from left - Samari, Karra, Kukhreni, Reu, Panchand, and right ‚¬œ Lothther and Manahari.West Rapti River:It locates in both the country, Nepal and India.Draining the Rapti Zone of Nepal, this river flows from the Mid-Western Region to the Awadh and Purwanchal regions of Uttar Pradesh state of India.Finally, it joins the major left-bank tributary of the Ganges, Ghaghara, known as Karnali inside Nepal.The tributaries are Lungri Khola, Jhimruk Khola, Ami River, and Rohini river.Additional InformationIndus:The Indus originates from the Bokhar Chu (glacier) on the northern slopes of Mt. Kailash.Jhelum, Chenab, Ravi, Beas, and Satluj are its main tributaries.The River passes by the Nanga-Parvat and turns southwest to enter Pakistan.Ganga:It is a transboundary river of Asia which flows through India and Bangladesh.The important tributaries are the Yamuna, the Ramaganga, the Gomti, the Ghagra, the Son, the Gandak, the Burhi Gandak, the Kosi and the Mahananda.At Farakka in West Bengal, the river divides into two arms namely the Padma which flows to Bangladesh, and the Bhagirathi which flows through West Bengal.Brahmaputra:It is known as the Yarlung Tsangpo in Tibet and the Dihang River in Arunachal Pradesh.It originates in the Manasarovar Lake region, near Mount Kailash.The principal tributaries of the river are the Lohit, the Dibang, the Subansiri, the Jiabharali, the Dhansiri, the Manas, the Torsa, the Sankosh, and the Teesta.