The district known for its rich iron ore deposits:

Chitradurga
Tumakuru
Ballari
Davangere

The correct answer is C. Ballari.

Ballari is a district in the Indian state of Karnataka. It is known for its rich iron ore deposits. The district is home to several iron ore mines, including the Kudremukh Iron Ore Company Limited (KIOCL) mine. The KIOCL mine is one of the largest iron ore mines in India. It has an estimated reserve of 2.1 billion tonnes of iron ore.

The iron ore deposits in Ballari are of high quality. They are low in impurities and have a high iron content. The iron ore from Ballari is used to produce steel in several steel plants in India.

The iron ore mining industry in Ballari has been facing several challenges in recent years. These challenges include environmental pollution, land acquisition, and social unrest. However, the government of Karnataka is taking steps to address these challenges. It has set up a task force to monitor the environmental impact of iron ore mining. It has also announced a compensation package for people who have been displaced by iron ore mining.

Despite the challenges, the iron ore mining industry in Ballari is still a major contributor to the economy of Karnataka. It provides employment to thousands of people and generates billions of rupees in revenue for the state government.