The correct answer is (a) Lalkuan.
Lalkuan is a town and a nagar panchayat in Udham Singh Nagar district in the Indian state of Uttarakhand. It is the headquarters of Lalkuan tehsil. The town is located on the banks of the Ramganga River, about 20 kilometers from the district headquarters of Rudrapur.
The paper mill at Lalkuan is one of the biggest in Uttarakhand. It was established in 1962 by the Uttarakhand Pulp and Paper Mills Limited (UPPCL). The mill has a capacity of producing 100,000 tonnes of paper per annum. It employs about 2,000 people.
The other options are incorrect. Khatima is a town and a nagar panchayat in Udham Singh Nagar district. Haridwar is a city in Haridwar district. Chakrata is a town and a nagar panchayat in Dehradun district.