Regarding the Delete Rule property, which of the following options does not guarantee referential integrity?

The Delete Rule property determines how the database handles referential integrity when a record is deleted in a relational data structure. When the option is set to "Ignore," it indicates that the database will not enforce any rules regarding the deletion of parent records that have dependent child records. In this case, if a parent record is deleted, any associated child records may remain in the database, potentially leading to orphaned records that no longer have a valid parent. This choice does not guarantee referential integrity because it allows for the existence of inconsistent relationships between the tables.

In contrast, the "Protect" option prevents the deletion of a parent record if there are still dependent child records, thereby ensuring that all relationships remain valid and consistent after a deletion operation. The "Delete" option automatically removes any dependent child records when a parent record is deleted, also maintaining referential integrity by cleaning up associated data. Therefore, the option that does not ensure referential integrity is indeed the one that allows for potential inconsistencies, which is "Ignore."