What does a worn strut often manifest as during a road test?

A worn strut directly affects the vehicle's ability to absorb shocks and maintain contact between the tires and the road. During a road test, this deterioration manifests as excessive bounce because the strut's damping ability has diminished. When shocks or bumps occur, the strut is unable to control the rebound effectively, leading to a situation where the vehicle oscillates up and down more than it should. This excessive bounce can compromise ride comfort and vehicle stability, making it an important indicator of strut condition.

The other options do not directly relate to the primary function of the strut. Increased ride height may occur due to other suspension issues, reduced braking power is typically related to brake components rather than struts, and wheel alignment issues are generally linked to other aspects of the steering or suspension system, rather than the strut's performance alone.