Final answer:
Confidentiality is the C.I.A. characteristic that ensures information is disclosed only to authorized users.
Step-by-step explanation:
The C.I.A. characteristic that ensures that only those with sufficient privileges and a demonstrated need may access certain information is Confidentiality. This is because confidentiality is concerned with preventing unauthorized access to information. It is a measure used to ensure that information is only disclosed to users who are authorized to access it.