Based on the tyre designation, when should you check the road-worthiness of your tyres?

You selected answers 1 and 2, which are both correct. In Germany, you are responsible for ensuring your tyres are roadworthy whenever you take over a vehicle from someone else and every time you change the tyres. These are key moments to check for damage, tread depth, age, and conformity with the correct tyre designation, since you cannot assume the previous user or the tyres themselves meet requirements. Regular checks at these times help ensure your safety and compliance with legal standards. Taking your own vehicle to a workshop does not always require a separate check if you are not changing tyres or taking possession of a new vehicle. Always check your tyres during these critical situations to avoid accidents and legal problems.