What is correct?

In this scenario, the presence of a traffic officer directing you at the crossroads indicates that you must follow their instructions. The correct action is to "Wait at the crossroads," as the officer is likely signaling for traffic to stop to ensure safety or to control the flow.

Not stopping when directed by a traffic officer is a violation of German traffic laws, which prioritize safety and compliance with signals from authorities. Additionally, turning without stopping could lead to dangerous situations if the officer is controlling traffic. Therefore, understanding the importance of following such directives is crucial for safe driving in Germany.