The correct answer is: D. Jharkhand
Jharkhand is a state in eastern India. It is the 14th largest state in India by area and the 30th most populous state. The state is bordered by West Bengal to the north, Odisha to the east, Chhattisgarh to the south, and Uttar Pradesh and Bihar to the west. The capital of Jharkhand is Ranchi.
Jharkhand is a mineral-rich state. It is the largest producer of coal in India, and also produces iron ore, bauxite, copper, and limestone. The state has a number of important industrial centers, including Jamshedpur, Bokaro Steel City, and Ranchi.
The gold mines in Bihar were located in Jharkhand during the seventeenth century. The mines were operated by the Mughal Empire, and they produced a significant amount of gold. The mines were closed in the eighteenth century, but they have been reopened in recent years.
The other options are incorrect because they are not located in Jharkhand. Champaran is a district in Bihar, Patna is the capital of Bihar, and Sasaram is a town in Bihar.