When the Cab train manned MCB is tripped, what is the effect?

When the Cab train manned MCB (Manned Control Box) is tripped, the primary effect is that the train is disabled if tripped in the active cab. This is a safety feature designed to prevent accidents or further issues when the operator is in a situation where they cannot safely control the train. Tripping the MCB usually indicates a need to halt operations due to a safety concern, such as an emergency or malfunction.

Disabling the train ensures that without proper control or oversight, the train will not proceed, thus minimizing the risk of accidents on the track. Other choices, such as the emergency brake applying or the train operating normally, do not accurately reflect the functionality of the MCB when it's tripped—the intent is entirely about ceasing all operations for safety.