What action is prohibited when the red lights at a railroad crossing are flashing?

When the red lights at a railroad crossing are flashing, it signals that a train is approaching, and crossing the tracks in this situation is prohibited. This is a critical safety measure designed to prevent accidents between vehicles and trains, which can be devastating. The flashing lights serve as a warning to drivers that they must stop and wait until the lights turn off and it is safe to proceed.

The other actions, such as parking near the crossing, slowing down to observe, or stopping before the crossing, may not be ideal but do not directly conflict with the safety guidelines related to the flashing lights. However, crossing the tracks during this signal poses a major risk and is strictly not allowed to ensure the safety of all road users.