Which conduct is right?

In the scenario depicted in the image, the green car must yield to traffic on its right according to German traffic rules. This is a crucial aspect of the right of way, which states that vehicles must yield to vehicles approaching from the right at intersections where there are no traffic signals.

Additionally, if you are turning, you may do so as long as you are observing the traffic signs and signals. It's important to ensure there are no oncoming vehicles or pedestrians before making the turn.

Choosing the correct combination (1 and 2) was important because it recognizes the obligation of the green car to yield and affirms that turning is permissible under the right conditions while adhering to traffic signs. The option that indicates you may only turn when the lights show "green" is not applicable here, as the context suggests the presence of yield signs, not traffic lights. Thus, understanding these rules helps maintain safe traffic flow and avoid accidents.