What does the following safety sign mean?
The arrow on a round blue indication sign tells vehicles which way they must go (Enforcement Rule, Appendix 6). Look at where the arrow splits and which way it points, and do not confuse it with the triangular caution sign for two-way traffic, which can look similar in meaning.
Answer: ③
Explanation
A blue circle with one arrow splitting upward to both sides is an indication sign instructing vehicles to pass on both sides (Enforcement Rule, Appendix 6, No. 312). It is placed on the right side or in the middle of the road at the point where vehicles must split and pass on both sides. A left-or-right-turn instruction has arrows bending sideways, two-way traffic is a triangular caution sign with up and down arrows, and passing on the right shows an arrow pointing down to the right, so the pictures differ.
Legal basis: 도로교통법 시행규칙 별표6 312 양측방통행표지