What applies when using driver assistance systems for longitudinal and lateral control of your vehicle?

Your answer is correct because according to German traffic rules, when using driver assistance systems for controlling speed and steering, it is essential to understand the system's limits (option 1). This means you must know when the system can and cannot function properly. Additionally, if the system malfunctions, you must immediately take back control; the system is not a substitute for the driver (option 2). On the other hand, relying solely on the system when tired is not permitted (option 3), as driver assistance systems do not replace driver alertness and responsibility. Always remain attentive and ready to intervene.