What is true here regarding the distance between you and the vehicle ahead?

In the context of the question regarding the distance between you and the vehicle ahead, your answer that includes options 1 and 2 is correct.

1. Regarding the truck and the yellow car, it's important to maintain a safe distance because the yellow car may attempt to switch back into your lane, which could lead to an emergency situation if you are too close. This reflects the principle of maintaining a safe following distance to allow for any unexpected movements from vehicles in front.

2. The second option emphasizes the responsibility of the yellow car to restore a safe distance as it merges back into your lane, ensuring that it does so when it is safe to do so. This aligns with German traffic laws that require drivers to be aware of their surroundings and the behavior of other road users.

The option you missed, which is the third one about the truck being too large compared to your bus, is also relevant. Understanding the size of vehicles around you is crucial because larger vehicles often have more significant blind spots and take longer to stop. Therefore, assessing the situation correctly is vital for safety.

The combination of all relevant choices helps emphasize the need for situational awareness and appropriate distance maintenance, which are key components of safe driving according to German traffic regulations.