What does this panel indicate on a dual carriageway?

A)That we are approaching an intersection within 300 metres.
B)That at 300 metres we can make a U-turn.
C)That at 300 metres the next exit is located.Correct
On a motorway, dual carriageway or road for motor vehicles, the sign indicates that there is an exit on the right approximately 300 metres ahead, since the diagonals rise from left to right. Furthermore, the sign will be located on the right of the roadway. If the exit were on the left, the sign we would find would be the following: