Explanation:

- Reliance Industries is a leading Indian conglomerate, known for its diverse operations in sectors like energy, petrochemicals, textiles, natural resources, retail, and telecommunications.

- Reliance was the first Indian company to reach a market valuation of ?10 lakh crore.

- BSNL, or Bharat Sanchar Nigam Limited, is a state-owned telecommunications company in India. It has faced financial difficulties and restructuring, and it is not listed on the stock exchange.

- Jio is a telecommunications company under the Reliance Industries umbrella, noted for revolutionizing the Indian telecom market with affordable plans and widespread 4G access.

- Airtel, or Bharti Airtel, is another major telecom player in India, but it hasn't reached the 10 lakh crore market valuation mark yet.