The correct option is Non-repudiation ensures a party cannot deny performing an action because of verifiable evidence such as digital signatures and tamper-evident ledger records.

Non-repudiation ensures a party cannot deny performing an action because of verifiable evidence such as digital signatures and tamper-evident ledger records describes the security property that binds actions to identities through verifiable evidence. Cryptographic techniques like digital signatures and tamper-evident logs provide proof that an action occurred and who performed it which makes it difficult for a party to plausibly deny their actions.

Cloud Audit Logs is the name of a logging service and it records events, but the service name alone is not the definition of non-repudiation. Logs can contribute to non-repudiation when they are protected and signed, but the option does not state the required verifiable cryptographic evidence.

Non-repudiation prevents malware infections and denial-of-service attacks against network systems is incorrect because those concerns relate to detection and prevention controls and to availability and integrity, which are different areas of security handled by anti-malware and network defenses rather than by non-repudiation mechanisms.

Non-repudiation guarantees that data will always be accessible to authorized users is incorrect because that statement describes availability. Availability is a separate security property and does not capture the attribution and evidence aspects that define non-repudiation.

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