When handling switches and derails, what is crucial for the intended route?

The effectiveness of switches and derails in ensuring a safe and correct route is fundamentally reliant on them being properly lined. When switches are lined correctly, they direct the railcars or train onto the desired track. This action is essential for maintaining the intended route and ensuring safe operations. If a switch is not lined accurately, it can lead to derailments or unintended track changes, posing significant safety risks.

The other options, while relevant to operational safety, do not directly affect the correctness of the routing in the same way. For instance, while switches being locked is important for safety and preventing accidental changes after they are set, it doesn’t directly pertain to the alignment for the immediate route intended. Similarly, while crew alignment and signal functionality are vital for overall safe train operations, they do not address the specific requirement for the switch to direct trains on the correct track. Properly lining the switches remains the crucial factor for ensuring that the intended route is safely achieved.