Which of the following statements about the bank rate is true?

The bank rate is the rate at which the central bank (such as the Reserve Bank of India) lends money to commercial banks in the country. It is a tool used by the central bank to control the money supply in the economy. When the central bank increases the bank rate, it becomes more expensive for commercial banks to borrow money from the central bank, which in turn reduces the money supply in the economy. Conversely, when the central bank decreases the bank rate, it becomes cheaper for commercial banks to borrow money from the central bank, which increases the money supply in the economy. Option A is incorrect as it refers to the repo rate, which is the rate at which banks borrow money from the central bank. Option C is incorrect as it refers to the lending rate of banks, which is different from the bank rate. Option D is incorrect as it refers to the reverse repo rate, which is the rate at which the central bank borrows money from commercial banks.