Towards North, the Pat region is drained by which river?

The correct answer is: B. North Koel river

The North Koel river is a tributary of the Son River in the Indian states of Jharkhand and Bihar. It originates in the Rajmahal Hills in Jharkhand and flows northwards through the districts of Deoghar, Godda, and Sahibganj before joining the Son River near Garhwa. The North Koel is a perennial river and is an important source of irrigation and drinking water for the region. It is also a popular destination for fishing and boating.

The other options are incorrect because:

• The Barakar river is a tributary of the Damodar River in the Indian state of Jharkhand. It originates in the Chhotanagpur Plateau and flows eastwards through the districts of Hazaribagh, Bokaro, and Dhanbad before joining the Damodar River near Bokaro Steel City.
• The Subarnarekha river is a major river in eastern India. It originates in the Chhotanagpur Plateau in Jharkhand and flows eastwards through the states of Odisha and West Bengal before joining the Bay of Bengal near Balasore.
• The Phalgu river is a tributary of the Ganga River in the Indian state of Bihar. It originates in the Himalayas and flows southwards through the districts of Nalanda, Patna, and Gaya before joining the Ganga River near Patna.