At what distance below the lining surface can disc pad rivets contact a rotor?

The correct answer is determined by understanding the components of a disc brake system. The rivets of disc brake pads are attached to the backing plate, and if they extend too far past the lining surface, they may make contact with the rotor when the brakes are applied.

The thickness of the disc pad backing plate represents the depth at which rivets can safely contact the rotor without causing damage or affecting braking performance. If rivets protrude beyond this thickness, it increases the risk of contact and potential wear or damage to the rotor surface, compromising the braking system's effectiveness and safety.

Additionally, the other options present specific measurements that do not account for the variability in backing plate thickness across different disc pad designs. Using the backing plate thickness as a guideline ensures compatibility with the rotor and maintains optimal brake function.