What is the correct action when approaching a roundabout?

When approaching a roundabout, yielding to traffic that is already in the roundabout is the appropriate action. This procedure ensures that vehicles within the roundabout have the right of way, facilitating smooth traffic flow and reducing the potential for accidents. By yielding, you allow those already circulating in the roundabout to pass before you enter, which helps maintain organized traffic movement and limits confusion.

The other options do not align with safe driving practices at roundabouts. Entering with speed could lead to dangerous situations, as it might not allow time for proper judgment regarding other vehicles. Stopping before entering would disrupt the flow of traffic inside the roundabout and could result in collisions. Making a U-turn is not a suitable action, as roundabouts are designed for continuous flow, not for reversing direction abruptly. Overall, yielding to existing traffic creates a safer environment for all road users.