What is the meaning of the following traffic sign?

- Correct answer: A path for bicycles only.
- Driver pay attention, bicycles passing.
- Designated lane for motorcycles and bicycles only.
- No entry for bicycles.
Why this is the answer
The correct answer in the official bank: A path for bicycles only.
A round blue sign is a mandatory sign, and the bicycle symbol on it marks a path for bicycles only. So other vehicles must not use this path as a road. A warning sign for bicycles is a triangle with a red border, and "No entry for bicycles" is shown as a circle with a red border.