Solution:Tata Steel Limited formerly Tata Iron and Steel Company Limited (TISCO) is an Indian multinational steel-making company headquartered in Mumbai, Maharashtra, and a subsidiary of the Tata Group. It was founded by Jamshetji Tata and established by Dorabji Tata.
Bharat Aluminium Company (BALCO) is one of the largest producers of aluminium situated on Chhattisgarh. BALCO has an integrated aluminium plant with captive bauxite mines, a captive power plant, refineries and smelters.
BALCO has proved its mettle by developing and supplying special aluminium alloys to the nation’s intermediate range ballistic missiles Agni and surface missiles Prithvi.
Bharat Petroleum Corporation Limited (BPCL) is an Indian state-controlled Maharatna oil and gas company headquartered in Mumbai, Maharashtra. The Corporation operates two large refineries of the country located at Mumbai and Kochi.
Bharat Electronics Limited (BEL) is an Indian state-owned aerospace and defence company with about nine factories, and several regional offices in India.