Explanation:

• Any money that flows out of RBI leads to increase in the money supply.
• When the RBI purchases government securities from Public, the money flows out of RBI, this will increase the money supply. So statement 1 is correct.
• When currency is deposited by public in commercial banks, its mere transfer of money from public to commercial banks. The net effect on the money supply is nil. So statement 2 is incorrect.
• When the Government borrows from RBI, the money again flows out of RBI. To fulfill the demand of the Government, RBI will print new money and this leads to increase in the money supply thus statement 3 is also correct.

Hence option 3rd is correct.