What is the rule created by the road markings in this situation?

You selected the correct answer. When specific road markings—such as a broad, interrupted line at a junction—are present but there is no explicit stop or yield sign, German traffic rules require drivers to approach the junction with caution. This means you must slow down, pay extra attention, and be prepared to react to cross traffic or other road users. However, you are not automatically required to stop or yield unless indicated by additional signs or markings. This rule helps prevent accidents at less-regulated intersections and ensures all drivers proceed safely. In future situations, always check for such markings and adjust your driving by approaching the junction cautiously.