What should be suggested when a deviation cannot be approved as requested and the situation permits?

When a deviation cannot be approved as requested, suggesting an alternative course of action is crucial for maintaining safety and efficiency. This approach allows the controller to proactively address the pilot's needs while still adhering to safety protocols and regulations.

Offering alternatives ensures that the pilot can still progress without significant delays or safety concerns. It reflects the controller's role in facilitating safe flight operations while considering air traffic management protocols.

In contrast, not responding to the request or ignoring it would not provide a resolution; consulting a supervisor might delay the decision-making process when immediate alternatives could be proposed instead; and delaying the decision could lead to confusion or operational delays, which are best avoided in air traffic situations. Thus, providing an alternative course of action is the most constructive and effective response in this scenario.