A 'Divided Highway Ahead' sign advises drivers to do what with regard to the median?

The 'Divided Highway Ahead' sign indicates that the road is about to change to a divided highway format, where two opposing lanes of traffic are separated by a median. This sign serves as a warning for drivers to prepare for this change, suggesting that they should keep to the right side of the road. In a divided highway, the median serves as a safety feature that helps prevent head-on collisions and organizes traffic flow.

By keeping to the right, drivers ensure they are on the correct side of the roadway, which aids in the smooth operation of traffic in both directions. The importance of this instruction is underscored by the median's role in maintaining safe distances between vehicles traveling in opposite directions.

Other options, such as keeping to the left, avoiding the median, or stopping before reaching the median, do not align with the standard practices on divided highways. Drivers should not deviate from the established flow of traffic by moving to the left or stopping unnecessarily, as this could create hazards for themselves and other road users.