Who can apply the inspection sticker if the mechanic is exempt from the road test?

The correct answer is that the exempted mechanic can apply the inspection sticker. In Pennsylvania, if a mechanic is exempt from performing the road test, it means they have already met certain qualifications or are working under specific circumstances that allow them not to conduct this part of the inspection. However, they retain the authority to perform the other parts of the state inspection process, including applying the inspection sticker to a vehicle that has successfully passed the required checks.

This authority is given because the exempted mechanic is still considered certified to perform safety inspections. Their experience and qualifications allow them to approve the vehicle for safety compliance, thus making it appropriate for them to apply the sticker themselves.

In contrast, options such as another certified mechanic could apply the sticker, but the question specifies that the mechanic in question is already exempt. The vehicle owner applying the sticker is not permitted, as they are not a certified inspector, and a trainee under supervision would also not have authority to do so independently. It's crucial that only certified mechanics complete the inspection process and affix stickers, maintaining the integrity of vehicle safety regulations.