Which acronym represents the four properties of a database transaction?

• A. Atomicity, Consistency, Isolation, Durability
• B. Durability, Isolation, Consistency, Atomicity
• C. Atomicity, Consistency, Isolation, Durability
• D. Consistency, Isolation, Atomicity, Durability

Answer: (C)

ACID properties define what a database transaction guarantees. Atomicity means a transaction is all-or-nothing—either every operation succeeds or none do. Consistency ensures that a transaction moves the database from one valid state to another, preserving integrity constraints. Isolation means concurrent transactions don’t interfere with each other, so the result appears as if transactions were executed one after another. Durability guarantees that once a transaction is committed, its effects persist even if the system crashes. The standard acronym comes from the initials of these four terms in that order: Atomicity, Consistency, Isolation, Durability. The option that lists these four terms exactly in that sequence matches the familiar acronym ACID. Other arrangements swap the order but still refer to the same properties, just not in the conventional acronym form.