If sector 67 cannot approve the block, what must the student do?

The correct answer indicates that if sector 67 is unable to approve the block, the student has the option to issue an alternative clearance without requiring the block. This action is crucial in maintaining the flow of air traffic while ensuring safety and compliance with operating procedures. By issuing an alternative clearance, the student can provide the pilot with a clear path forward, allowing them to continue their flight operations without unnecessary delays.

This course of action reflects a proactive approach to air traffic management, ensuring that pilots are still able to operate efficiently even in situations where a specific block cannot be approved. It demonstrates an understanding of the dynamics of air traffic control, where flexibility and quick decision-making are essential for effective operations.

In contexts where other answers are considered, options such as delaying departure or waiting for an approval might not adequately address the urgent nature of air traffic movements and could lead to increased congestion or safety concerns. Similarly, seeking a different block from another sector may not be feasible depending on the airspace and operational constraints at that moment. Hence, the issuance of an alternative clearance is the most appropriate and effective response in this scenario.