What is the right course of action?

In this scenario, it’s crucial to consider the interactions between vehicles and other road users, such as the red truck and the cyclist.

As per German traffic rules:

1. If you are the first to approach the junction, you have the right of way, meaning you can proceed without yielding to the other vehicles unless specified by traffic signals or signs.

2. However, if the red truck is turning, you must allow it to complete its maneuver before proceeding, as vehicles making a turn often have priority, especially if there are no signs indicating otherwise.

3. Additionally, cyclists generally have specific rights at junctions. If the cyclist is also turning, they may need to be given priority, especially if they have a clear path and you do not.

Therefore, the correct action combines all these factors: proceeding when it's safe, yielding to the red truck and allowing the cyclist to turn. Recognizing all involved parties ensures safe navigation through the junction according to German traffic regulations.