An Intranet is a private network that is accessible only to an organization’s personnel. It is used for internal communication, data sharing, and collaboration while ensuring security and restricted access.

Let’s analyze each option:

Option A: An extranet

Incorrect. An extranet extends an organization’s internal network to external parties such as vendors, suppliers, or business partners. Since the organization wants to allow access only to its personnel, an extranet is not the right choice.

Option B: A local area network (LAN)

Incorrect. While a LAN is a network within a limited geographic area (such as an office), it does not necessarily restrict access only to personnel. Additionally, an intranet operates over a LAN but includes access controls and authentication mechanisms.

Option C: An Intranet

Correct. An intranet is specifically designed for internal use, allowing employees to securely share documents, collaborate, and access internal resources. Organizations can implement access control mechanisms to restrict access to authorized personnel only.

IIA Reference: Internal auditors assess IT security to ensure that internal networks (such as intranets) have appropriate access restrictions to protect sensitive data. (IIA GTAG: Auditing IT Networks)

Option D: The internet

Incorrect. The internet is a public network that does not restrict access. Using the internet for internal communication would expose sensitive data to external threats.

Thus, the verified answer is C. An Intranet.