What flight time must be recorded by a pilot exercising the privileges of a commercial certificate?

A pilot exercising the privileges of a commercial certificate must log flight time that meets the requirements for obtaining a certificate, rating, or review. This specifically includes time that demonstrates proficiency and experience in the relevant aircraft category and class, which is essential for ensuring safety and adherence to regulatory standards.

Logging flight time related to obtaining a certificate or rating is crucial because it provides a structured way to track the experience necessary for meeting the qualifications set by aviation authorities. This may include time spent undergoing flight training, solo hours, or time serving as pilot-in-command for qualifying flights.

The other options do not adequately cover the requirements. Simply logging any flight time over 10 hours does not reflect the necessary training or experience for commercial certification. Focusing only on flight time related to currency ignores the broader training needs for progression in a pilot's career. Logging time in a multi-engine aircraft is only a specific subset of flight time and does not fulfill the broader requirement to document all relevant experience necessary for certification or rating achievement.