What is the outcome of successful authentication?

Successful authentication primarily results in the confirmation of a user's identity. This process is essential in security systems, ensuring that only authorized individuals can access specific resources or data. When a user provides their credentials, such as a password or biometric information, the system verifies this information against its records. If it matches, the system confirms the identity of the user and allows them to proceed with the intended action, whether that involves accessing secure areas of a system, retrieving sensitive data, or using particular software functionalities.

The other options would not encapsulate what authentication achieves. For instance, while full access may be granted based on successful authentication, it does not solely define the outcome of the authentication process itself. Likewise, the installation of utility programs or the prevention of viruses relates to different aspects of computing and security management, rather than the primary function of verifying a user's identity.