What is the right thing to do?

In this scenario, the correct response involves understanding right-of-way rules.

Firstly, you must yield to the green car because it is traveling straight in a situation where vehicles on the main road have the right of way. By allowing the green car to proceed, you're following the rule that requires drivers to give way to vehicles continuing on their course.

Additionally, you should recognize that the red car, which appears to be pulling out or preparing to turn, may also present a situation where you need to allow it to pass safely, depending on its position and your intended direction.

This context emphasizes the importance of assessing all vehicles' movements and appropriately yielding to those with priority, ensuring traffic flows smoothly and safely in accordance with German traffic laws.