When you see the letters 'RR' painted on the pavement, you are approaching:

When you see the letters 'RR' painted on the pavement, it indicates that you are approaching a railroad crossing. This marking serves as a visual alert to drivers that they need to be cautious and prepared to stop, as trains may be crossing the road ahead. The 'RR' stands specifically for "railroad" and is a standard symbol used to enhance safety by increasing the visibility of railroad crossings to drivers, especially in areas where the crossings might not have signals or gates. Recognizing this marking is essential for ensuring safe driving practices near train tracks, as failure to yield to an oncoming train can lead to severe accidents.

The other options do not relate to the 'RR' marking: a speed limit sign does not feature these letters, a pedestrian zone would typically have different markings to denote the presence of pedestrians, and a yield sign is represented by a triangular shape rather than painted letters.