Option 1 -> ₹50 represents only 5% of deposits, which is incorrect.
Option 2 -> ₹500 is the amount remaining after keeping 50% CRR, which is correct.
Option 3 -> ₹100 represents only 10% of deposits, which is incorrect.
Option 4 -> ₹1000 would mean no reserve is maintained, violating the 50% CRR requirement.
Hence, Option 2: ₹500 -> When CRR is 50%, the bank must keep 50% of deposits (₹500) as reserves with the central bank. The remaining 50% of deposits (₹1000 - ₹500 = ₹500) can be used for giving loans to customers. This is calculated as: Loanable Amount = Deposits × (1 - CRR) = ₹1000 × (1 - 0.50) = ₹500 -> correct