Which statement correctly describes a road marking that indicates "no waiting at any time"?

The statement that describes a road marking indicating "no waiting at any time" is that no waiting is allowed regardless of the time. This means that drivers must not stop their vehicles in that area for any prolonged period, as it is strictly prohibited. The purpose of this type of marking is to ensure that traffic flow is maintained and to reduce congestion or potential hazards that could arise from vehicles stopping unexpectedly.

The other options do not align with the definition of the marking. For example, the idea that waiting is always allowed contradicts the intended message of the no waiting sign. Similarly, the concepts that stopping is only permitted for loading or that parking is allowed if vehicles are attended imply some level of tolerance for stopping or waiting, which the marking clearly does not permit. Only the statement indicating a complete prohibition of waiting aligns with the intended regulation of the road marking.