Which one of the following is NOT a part of the ACID properties of database…

Key idea: ACID describes four core properties of database transactions: Atomicity, Consistency, Isolation, and Durability.

• Atomicity: the transaction is all-or-nothing; either all its changes are applied or none are.

• Consistency: a transaction moves the database from one valid state to another, preserving integrity constraints.

• Isolation: concurrently executing transactions do not interfere with each other; results are as if transactions ran serially.

• Durability: once a transaction commits, its changes are permanent and will survive system failures.

Deadlock-freedom is not part of ACID; it is a property related to concurrency-control algorithms (how a system avoids or resolves deadlocks) rather than one of the transactional guarantees listed by ACID.