Which system allows external users to access an organization's network with valid credentials?

The correct answer is the extranet, as it is specifically designed to enable controlled access to certain parts of an organization’s network by external users who have valid credentials. An extranet extends the intranet, which is typically restricted to internal users only, to allow suppliers, partners, or other stakeholders to access shared resources, documents, and applications in a secure manner.

This setup facilitates collaboration and communication between the organization and its external entities while maintaining a layer of security that protects sensitive internal information. It often uses secure protocols to ensure that data being transmitted remains confidential.

In contrast, the internet generally refers to the global network that is available to anyone without restrictions. The intranet is limited to internal users of a specific organization, and a local area network (LAN) connects computers within a limited geographic area, such as a single building, and is not designed for external access.