Which description of the following traffic safety sign is correct?

Answer: ① Roundabout sign

Three arrows chasing each other in a circle mean a roundabout ahead. The sign is placed on the right side of the road 30-120 m before the intersection. Slow down and give way to vehicles already in the roundabout. [Enforcement Rules of the Road Traffic Act, Annex 6, Caution sign No. 109]