What is the consequence of not having a green signal from the Block Operator?

The correct answer is that not having a green signal from the Block Operator indicates a stop signal. In the context of railway operations, a green signal typically signals that it's safe for a train to proceed. Conversely, if a green signal is not displayed, this signifies that a train should not continue and must either stop or prepare for a signal that may require them to halt.

The absence of a green signal often correlates with various situations including a stop signal—this could mean there are issues further down the track, another train occupying the block, or other safety concerns that require the train to halt to prevent accidents. Therefore, understanding that a missing green signal translates directly into a stop signal is crucial for maintaining safe and efficient train operations. Proper adherence to signals is essential for the overall safety of the train, crew, and passengers.