What is meant by "blocking" in train operations?

Blocking in train operations refers specifically to the arrangement of railcars for safety and efficiency. This process involves organizing the railcars in a train according to specific criteria, which can include the type of cargo, weight distribution, or destination. Proper blocking is crucial as it affects how the train handles while in motion, ensuring that heavier cars are positioned in a way that maintains stability and reduces the risk of derailment. It also allows for a more efficient unloading process at the destination, as cars can be arranged to facilitate quicker access to the necessary cargo.

The other options do not accurately represent the concept of blocking. For instance, unloading trains does not define the configuration of cars; separating car types relates to categorizing them rather than ordering them for movement. Lastly, the notion that blocking is unrelated to operations contradicts its integral role in safe and efficient train management.