Answer:
A. already in the roundabout
Explanation:
A roundabout consists of the meeting of two or more streets around a circle. That way, cars on the roundabout will be able to choose one of the streets to follow their course. When you arrive at a roundabout, you must yield to the cars that are already at the roundabout. This is necessary because by traffic laws, the car that is already at the roundabout has preference over the others. When the cars pass and the roundabout is empty, you can enter the roundabout and continue your journey.
