What is the meaning of the following traffic sign?

1. In the intersection ahead only left U-turn is permitted.
2. Correct answer: Give right-of-way to traffic crossing your path within the roundabout and pass the roundabout from its right side.
3. You have right-of-way in the roundabout, and pass the roundabout from its right.
4. Pass the place that is marked in the signpost from its left only.

WhyA blue circle with arrows around it is sign 303: give way to those already in the roundabout and drive around it to the right. There are no yellow arrows here.