In Indian industrial geography, which region is popularly known as the Ruhr of India because of its dense concentration of coalfields, power projects and heavy industries?

Introduction / Context:
Indian geography often uses industrial nicknames such as Ruhr of India to highlight regions that resemble famous industrial areas in other countries. Ruhr is a heavily industrialised coal and steel belt in Germany, so this question checks whether the learner remembers which Indian river valley plays a similar role in terms of coal, power generation and heavy industry.

Given Data / Assumptions:
• The question asks which region is called the Ruhr of India. • Four major Indian industrial regions are listed as options. • Only one region is a coal rich river valley with a very high density of heavy industries.

Concept / Approach:
The Ruhr of India must be an area where coal mining, thermal and hydel power generation, iron and steel plants and engineering units are strongly concentrated. Standard geography texts clearly associate this nickname with the Damodar Valley region in eastern India, where the Damodar River and surrounding coalfields provide the basis for a classic heavy industrial belt.

Step-by-Step Solution:
Step 1: Recall that the Damodar River flows mainly through Jharkhand and West Bengal and that its valley contains many rich coalfields. Step 2: Remember that the Damodar Valley Corporation has developed a series of dams and power projects, and that several major steel and engineering plants lie in this belt. Step 3: Compare this pattern with the Ruhr region in Germany, which is also a coal based heavy industrial valley, and recognise that this similarity is the reason for the nickname Ruhr of India.

Verification / Alternative check:
A quick check in reliable school or exam reference books confirms that the Damodar Valley region, and not the other options, is described as the Ruhr of India. The remaining options refer to important industrial corridors, but none is primarily a coalfield based river valley with the same classic profile.

Why Other Options Are Wrong:
Option A (Mumbai–Pune industrial region) is a diverse coastal industrial corridor with ports, petrochemicals and services, rather than a coal based river valley. Option C (Chennai–Bengaluru industrial region) is known for automobiles, textiles and information technology, but not for dense coalfields similar to the Ruhr. Option D (Delhi–Kanpur industrial region) is an important manufacturing belt in north India, but it does not match the typical coal and heavy industry pattern of the Ruhr.

Common Pitfalls:
• Learners sometimes choose Mumbai–Pune simply because it is very famous, without focusing on the coalfield based nature of the Ruhr comparison. • Some students also confuse Ruhr of India with the older phrase Sorrow of Bengal, which refers to flooding by the Damodar River, not to its industrial role.

Final Answer:
Therefore, the region known as the Ruhr of India is the Damodar Valley region.