The _______ River is known as the 'Sorrow of Bihar'.
- Gandak
- Kosi
- Bagmati
- Son
Answer: Kosi
The Kosi River is known as the 'Sorrow of Bihar' due to its frequent flooding and course changes, causing widespread destruction. It originates in Nepal and joins the Ganga in Bihar. The Kosi Project aims to control floods and provide irrigation.