Q. Which river's main stream is called 'Niranjana'?
Answer: Phalgu
Notes: The Niranjana River flows from Chatra district, Jharkhand, northward into Bihar. It joins the Mohana River near Gaya to form the Phalgu River. The river is also known as Lilajan or Nilanjan in its upper stretches. Kanhar, Sankh, and Ajay are distinct rivers and do not have the main stream called Niranjana.