Explanation:

- The Central Bank of India was established in 1911 and is one of the oldest and largest commercial banks in India.

- Option 1: Commercial Banks

- Commercial banks are financial institutions that offer banking services like accepting deposits and providing loans to individuals and businesses.

- The Central Bank of India fits into this category as it operates retail-banking functions across the country.

- Correct Answer.

- Option 2: Central Bank

- A central bank regulates a country's money supply and monetary policy.

- The Reserve Bank of India (RBI) acts as the central bank for the country, not the Central Bank of India.

- Option 3: Private Bank

- Private banks are owned by private individuals or business entities.

- The Central Bank of India is not privately owned but is a public sector bank.

- Option 4: None of these

- This option doesn't apply as the Central Bank of India is indeed a commercial bank.