The correct answer is: B. Guard
The guard is responsible for the safety of the train and its passengers. They are the only person who is allowed to operate the train’s brakes. The guard must be present in the brakevan when the train is being shunted from one line to the other to ensure that the train is safe and that the brakes are properly applied.
The driver is responsible for the operation of the train. They are not responsible for the safety of the train or its passengers. The driver does not need to be present in the brakevan when the train is being shunted from one line to the other.
The ALP is an assistant to the driver. They are not responsible for the safety of the train or its passengers. The ALP does not need to be present in the brakevan when the train is being shunted from one line to the other.
None of these is the correct answer because none of these people are responsible for the safety of the train and its passengers.