Which of the following is the process of rewriting source and destination addresses of IP packets as they pass through a router or firewall?

NAT is the broad umbrella term for the entire address translation technology family, not the specific mechanism for rewriting both source and destination addresses.

Supernetting is the technique of aggregating multiple contiguous network prefixes into a single larger route summary, which has no relation to address translation.

SNAT, or Static NAT, creates a persistent one-to-one mapping between an internal IP address and an external IP address, rewriting the source address on outbound packets and the destination address on inbound return packets. This bidirectional address rewriting at the packet level as traffic passes through a network device is exactly what the question describes. Unlike dynamic NAT or PAT, SNAT maintains a fixed configured mapping that translates both source and destination addresses depending on traffic direction.

PAT (Port Address Translation) maps many internal addresses to a single external IP using unique port numbers to track sessions, which differs from the direct IP address rewriting described.