An inappropriate speed is...

Correct answer: one that is not suited to the traffic, road, or driver conditions.

A speed is inappropriate for the conditions when it does not suit the traffic, the road, or your condition, even if you are not exceeding the speed limit. In the image, the sign allows 120 km/h, but there is snow on the roadway, and at that speed you would have trouble controlling the car. The maximum permitted speed can be appropriate when conditions are favorable.

Manual II. Cuestiones de Seguridad Vial, edición 2026 · Reglamento General de Circulación (RD 1428/2003)