In South Dakota, what should a driver do when approaching a roundabout?

Answer: B — Yield to traffic already in the roundabout

When approaching a roundabout in South Dakota, it is essential for drivers to yield to traffic that is already in the roundabout. This behavior ensures a smooth flow of traffic and helps prevent collisions. Roundabouts are designed for continuous movement, allowing vehicles already circulating to maintain their speed while newcomers yield. By yielding, a driver can safely assess the situation and enter the roundabout when there is an adequate gap, promoting safety and efficiency. Speeding up to enter quickly can lead to dangerous situations as it conflicts with the yielding requirement. Always stopping before entering is unnecessary and can disrupt the flow of traffic, negating the roundabout's benefits. Changing lanes before entering is also incorrect since it can cause confusion and potential accidents; the correct approach is to enter the roundabout from your current lane without changing it, unless signs specifically indicate otherwise. Therefore, yielding to traffic already in the roundabout is the safest and most effective action a driver can take.