Thermal power station Kahalgaon is located at which district in Bihar?

The correct answer is option (A), Bhagalpur.

Thermal power station Kahalgaon is located in Kahalgaon town in Bhagalpur district of Bihar. It is one of the largest thermal power stations in India. The power station is owned and operated by NTPC Limited. It has an installed capacity of 2,100 MW. The power station uses coal as fuel.

The other options are incorrect. Option (B), Banka, is a district in Bihar. Option (C), Vaishali, is a district in Bihar. Option (D), Kaimur, is a district in Bihar.