To ensure safe operation, train operators must monitor which type of systems?

Train operators must monitor both propulsion and braking systems to ensure safe operation. The propulsion system is responsible for moving the train forward and controlling its speed, while the braking system is crucial for slowing down or stopping the train efficiently and safely. It is vital for operators to have a comprehensive understanding of both systems, as any malfunction or oversight in either one can lead to hazardous situations.

Monitoring only the propulsion systems would ignore the critical aspect of halting the train when necessary. Conversely, focusing solely on the braking systems would neglect the equally important function of moving the train. Both systems must be monitored in conjunction to maintain overall safety and performance during operation. Therefore, the correct approach involves comprehensive awareness and oversight of both systems to ensure safety and efficiency in train operations.