Which system is crucial for network users to manage their credentials effectively?

Single Sign-On (SSO) is pivotal for network users because it streamlines the authentication process, allowing individuals to access multiple applications with a single set of credentials. This greatly enhances user convenience, as users do not need to remember and input different usernames and passwords for each service they use. By reducing the number of times credentials are entered, SSO also minimizes the risk of password fatigue, which can lead to poor password security practices such as using the same password across multiple sites or writing passwords down.

Moreover, SSO improves administrative efficiency, as it centralizes user authentication processes, making it easier to manage user accounts and enforce security policies. This can be particularly beneficial in environments where users need access to a range of enterprise applications, as it also simplifies the process of onboarding and offboarding users.

In contrast, other choices serve different but important roles in network security; for instance, Network Access Control focuses on enforcing security policies and device compliance, Identity Federation facilitates the sharing of identity information across different domains, and Virtual Private Networks (VPNs) provide secure remote access to a network but do not directly manage user credentials in the manner SSO does.