What is the meaning of the following traffic sign?

- Crossroad ahead.
- Merging of a roadway having right-of-way with a side road to its right (turning to the side road is allowed).
- Correct answer: You are approaching a side road merging from the right (turning right is prohibited). You have right-of-way over traffic coming from the side road.
- Give right-of-way to traffic coming from the road that merges from the right.
Why this is the answer
The correct answer in the official bank: You are approaching a side road merging from the right (turning right is prohibited). You have right-of-way over traffic coming from the side road.
The thick line in the sign stands for the road you are driving on, and the thin line joining it diagonally from the right stands for a side road that merges into it. The sign tells you that you are approaching a merge: turning into the side road is prohibited, and traffic coming from the side road must give you right-of-way.