The objective of concurrency control in a database system is to:

A.
restrict updating of the database to authorized users.

B.
prevent integrity problems when two processes attempt to update the same data at the same time.

C.
prevent inadvertent or unauthorized disclosure of data in the database.

D.
ensure the accuracy, completeness and consistency of data.

Explanation:
Concurrency controls prevent data integrity problems, which can arise when two update processes access the
same data item at the same time. Access controls restrict updating of the database to authorized users, and
controls such as passwords prevent the inadvertent or unauthorized disclosure of data from the database.
Quality controls, such as edits, ensure the accuracy, completeness and consistency of data maintained in the
database.