Q-77. You are the credit risk manager for a bank and are looking to mitigate counterparty credit risk exposure to ABCD, an A-rated firm. Currently your bank has the following derivatives contracts with ABCD:

| Contract | Contract Value (HKD) |

|----------|----------------------|

| A | 20,000,000 |

| B | 30,000,000 |

| C | 14,000,000 |

| D | 1,000,000 |

With the information provided, what is the most appropriate credit risk mitigation technique in this case?