What should drivers do during a heavy downpour with limited visibility?

Answer: C — Pull off the road and wait for the rain to let up

During a heavy downpour with limited visibility, the most advisable action for drivers is to pull off the road and wait for the rain to let up. This choice is critical for safety because driving in such conditions can significantly increase the risk of accidents, as visibility is greatly reduced, and the road may become slick or flooded. By pulling off to a safe location, such as a parking lot or a rest area, drivers can avoid hazardous situations until conditions improve. Other options may pose risks. Continuing to drive cautiously might not be sufficient, as the inability to see clearly can lead to misjudgments and the potential for collisions. Using high beams in heavy rain can actually worsen visibility, as the light reflects off the rain droplets, creating glare. Driving in the opposite direction is not a practical solution and could create dangerous situations for both the driver and others on the road. Therefore, the safest and most sensible approach is to wait for the rain to ease before continuing.