Drivers may open car doors on the side on which traffic is moving only when it can be done safely and without interfering with traffic. True or False?

The statement is true because it emphasizes the importance of safety and awareness of surrounding traffic conditions when opening a car door. Drivers should always ensure that it is safe to open their doors before doing so, particularly when traffic is moving alongside them. This means checking for oncoming vehicles or cyclists that could be affected and ensuring that the door can be opened without obstructing the flow of traffic. It is crucial to perform this action with consideration for others on the road, which can help prevent accidents and injuries.

The other choices suggest limitations or conditions that are either unnecessary or may not fully encompass safe driving practices. Therefore, the correct understanding is that openness of car doors must solely prioritize safety and not interfere with traffic at any time.