What should the train do after receiving permission to pass a signal?

After receiving permission to pass a signal, the train should travel at restricted speed to the next signal. This protocol ensures that the train can respond to any unforeseen circumstances, such as encountering a stop signal or oncoming traffic, enabling the engineer to stop safely if necessary.

Restricted speed typically means operating at a speed that allows the crew enough time to react to potential hazards, ensuring safety in scenarios where signaling is not clear. This procedure is in place to maintain safe operations while allowing trains to move when signals permit, thereby balancing efficiency with safety. It reinforces the importance of caution even when permission to proceed is granted.

The other responses do not align with the safety protocols enforced in train operations. For instance, proceeding at full speed disregards the safety precautions needed after passing a signal. Returning to the last station is unnecessary since the train has received permission and is not required to retrace its path. Stopping and waiting for further instructions may delay operations and is not warranted once permission has been granted if conditions allow for safe movement.