What type of usability test is conducted where a test administrator is present with the test participant in real-time?

A moderated usability test is characterized by the presence of a test administrator alongside the test participant during the testing session. This allows for real-time interaction, where the administrator can prompt or ask questions, clarify instructions, and observe participant behavior as it unfolds. The administrator's involvement enhances the quality of feedback and insights gathered, as they can probe for deeper understanding based on the participant's actions and responses.

In contrast, unmoderated usability tests do not involve a test administrator during the session, meaning participants carry out tasks independently. This setup can limit the depth of insights since there is no immediate opportunity for follow-up questions or clarifications. Remote usability tests may also be unmoderated or moderated but focus on the testing being conducted away from a controlled lab environment, which can include remote observation without direct interaction. Observational studies, while also involving observation of user behavior, tend to focus more on passive data collection rather than guided testing with interaction.

The active engagement of a moderator in the test process is what distinctly qualifies a moderated usability test, making it the correct answer in this context.