Which of these is a function of the Reserve Bank of India?

1. The central bank issues currency and controls money supply. 2. It also acts as banker to the government and to the banking system. 3. It is additionally the **custodian of the country's foreign exchange reserves**. 4. Income tax collection and company audit sit with other bodies entirely. _Source: NCERT Class 12 Introductory Macroeconomics, Ch 3 "Money and Banking", section 3.2 DEMAND FOR MONEY AND SUPPLY OF MONEY_