Which city is called the steel city of Karnataka?

The city in Karnataka that is often referred to as the "steel city" is Bellary. Bellary is known for its significant iron and steel industry and mining activities. It has played a crucial role in the development of the steel industry in Karnataka.

Now, let's clarify the options provided:

Option A: Bengaluru - Bengaluru is the capital city of Karnataka and a major metropolitan area, but it is not known as the steel city.
Option B: Mysuru - Mysuru is a prominent city in Karnataka known for its cultural heritage and tourism attractions, but it is not known as the steel city.
Option C: Bellary - Bellary is often referred to as the steel city of Karnataka due to its significant iron and steel industry.
Option D: Hubballi - Hubballi is a city in Karnataka but is not known as the steel city.
So, the correct answer is Option C: Bellary, which is called the steel city of Karnataka.