The correct answer is: Coal mining.
Jharia is a town in the Indian state of Jharkhand. It is located in the Dhanbad district, about 200 kilometers from the state capital, Ranchi. Jharia is one of the oldest and largest coal mining towns in India. The town was founded in the 18th century by the Raja of Jharia, who granted a lease to the East India Company to mine coal in the area. Coal mining has been the main economic activity in Jharia for over 200 years. The town is home to several large coal mines, including the Jharia Coalfield, which is one of the largest coalfields in India.
Coal mining has had a significant impact on the environment and the people of Jharia. The mining has caused extensive deforestation and land degradation. The coal dust from the mines has also caused air pollution and respiratory problems for the people of Jharia. In recent years, there have been several fires in the coal mines in Jharia, which have displaced thousands of people.
Despite the environmental and social problems caused by coal mining, it remains the main economic activity in Jharia. The town is home to a large number of coal miners and their families. Coal mining provides employment for a large number of people in Jharia and is a major source of revenue for the state government.
The other options are incorrect because:
- Textile production is not a major industry in Jharia.
- Indigo cultivation is not a major crop in Jharia.
- Religious pilgrimage is not a major tourist attraction in Jharia.