The correct answer is: b) Kosi.
The Kosi River is a major river in northern India and eastern Nepal. It is the fifth-longest river in India, and the largest tributary of the Ganges. The Kosi River is known as the “Sorrow of Bihar” due to its history of devastating floods. The river has changed course many times over the centuries, and has caused widespread damage to crops and property. In 1954, a major flood caused by the Kosi River displaced over 2 million people.
The other options are:
- a) Ganga: The Ganga River is the longest river in India and one of the most sacred rivers in Hinduism. It is also known as the “Mother Ganga”. The Ganga River does not cause as much flooding as the Kosi River.
- c) Gandak: The Gandak River is a major river in northern India and eastern Nepal. It is a tributary of the Ganges. The Gandak River does not cause as much flooding as the Kosi River.
- d) Son: The Son River is a major river in central India. It is a tributary of the Ganges. The Son River does not cause as much flooding as the Kosi River.