Which of the following is the GREATEST risk if two users have concurrent access to the same database record?

Entity integrity ensures that each record has a unique primary key and that the primary key is never null, which is not directly threatened by concurrent access to an *existing* record.

Availability integrity refers to the data being accessible when needed, and concurrent access doesn't inherently prevent availability, although conflicts can cause temporary delays.

Referential integrity ensures that relationships between tables are maintained (e.g., foreign keys reference valid primary keys), which is not the primary risk of concurrent updates to a *single* record.

The greatest risk if two users have concurrent access to the same database record is data integrity, as simultaneous modifications without proper concurrency control can lead to lost updates, inconsistent data, or corrupted information. This means one user's changes might overwrite another's, or the final state of the record might not accurately reflect the intended operations from both users, thus compromising the accuracy and consistency of the data.