In the production of the following in India, Bihar has monopoly in –

The correct answer is: B. Coal

Bihar is the largest producer of coal in India, accounting for over 30% of the country’s total production. The state has a number of large coal mines, including the Jharia coalfield, which is one of the largest in Asia. Coal is a major source of energy in India, and it is used to generate electricity, power industries, and fuel transportation.

The other options are incorrect for the following reasons:

• Limestone is produced in a number of states in India, including Rajasthan, Gujarat, and Madhya Pradesh.
• Pyrite is produced in a number of states in India, including Andhra Pradesh, Karnataka, and Tamil Nadu.
• Graphite is produced in a number of states in India, including Andhra Pradesh, Jharkhand, and Madhya Pradesh.