In India the steel production industry requires the import of

The correct option is coking coal.

To understand why coking coal is required for import by the Indian steel industry, we can look at the metallurgical process of steel production and India's natural resources:
1. Role of Coking Coal: Coking coal is a vital raw material used as a reducing agent and fuel in blast furnaces to convert iron ore into pig iron, which is then processed into steel. Unlike thermal coal used for power generation, coking coal has specific properties (like caking ability and low impurities) necessary for metallurgy.
2. India's Domestic Availability: While India possesses vast reserves of iron ore and thermal coal, it has a severe shortage of high-grade metallurgical coking coal. The domestic coking coal in India generally has a high ash content, making it unsuitable for direct use in modern blast furnaces without blending.
3. Necessity of Import: To sustain its massive steel production and maintain quality standards, India is heavily dependent on imports of high-quality coking coal, primarily sourcing it from countries like Australia, South Africa, and the USA.
4. Other Options: Saltpeter (potassium nitrate) and rock phosphate are not key raw materials required in large quantities for the primary iron and steel making process, making coking coal the correct and critical import requirement.