Explanation:

- Option 1: Bank rate is indeed a rate at which the central bank gives credit to commercial banks. It's the rate at which the central bank lends funds to financial institutions with no collateral requirement.

- Option 2: Bank rate and interest rates are different. Bank rate refers to the base rate set by the central bank, while interest rates include the rates charged by commercial banks to borrowers.

- Option 3: Bank rate is considered the discount rate of the central bank. When the central bank changes this rate, it affects the broader economy through lending rates.

- Option 4 (All the above): Since all the statements are true and interrelated, this option is correct.