Option 3: 675 -> M4 is calculated as M3 + Total deposits with Post Office Savings Organizations. First, we calculate M3 = M1 + Net time deposits = 375 + 250 = 625 crores. Then, M4 = M3 + Post Office deposits = 625 + 50 = 675 crores. M4 represents the broadest measure of money supply in the economy. -> correct