When may drivers cross the tracks of an unguarded railroad crossing marked by a flashing light?

The correct answer highlights the importance of adhering to safety regulations at unguarded railroad crossings marked by flashing lights. Drivers may only cross the tracks after the flashing red light has gone out, indicating that it is safe to do so. This safety measure ensures that the driver is not only aware of an approaching train but also confirms that it has fully passed and that the tracks are now clear of any hazards.

Crossing the tracks immediately after a train has passed could pose a risk, as other trains may be following closely behind, or it may be difficult for the driver to fully assess the situation even if one train has just cleared the tracks. This emphasizes the need for caution and patience.

While the option about crossing when no train is in sight might seem reasonable, it doesn't consider the potential for a train that could be approaching or hidden from view. Similarly, crossing only if the tracks are clear does not provide the specific assurance that the flashing red light signifies that it is safe to proceed. Therefore, waiting for the flashing light to cease is the most reliable indicator for safe crossing at an unguarded railroad crossing.