What should you be prepared for now?

The correct answer is that you should be prepared for the yellow car to exit the motorway. On German motorways (Autobahnen), when you see a vehicle in the middle lane approaching an exit, often indicated by position and lane choice near exit signs, it is common for that vehicle to change lanes to the right in order to leave the motorway. You must anticipate this maneuver so you can react safely, such as by adjusting your speed or position if necessary.

In this scenario, you should not expect the motorbike to exit, since it is in the left lane and not signaling or positioned near the exit. The blue bus ahead is not showing signs (like brake lights) or behavior indicating sudden braking, so that is not an immediate concern.

This anticipation of another vehicle’s lane change is a key defensive driving principle, especially near motorway exits. Always read the traffic situation and the positions of other vehicles, so you're ready if someone decides to exit or change lanes unexpectedly.