Which flow action can be used to wait for an external response?

The Flow Pause action is specifically designed to temporarily halt the flow's execution until a specified condition is met or an external response is received. This feature is essential in scenarios where the flow depends on input or confirmation from an external source, allowing for a synchronous interaction with external systems or services.

When a Flow Pause action is implemented, it effectively places the flow in a state of suspension, waiting for an event or signal to proceed. This can be particularly useful in processes requiring user confirmation, callbacks from APIs, or waiting for a particular time frame to elapse. Since the Flow Pause is designed for this exact purpose, it becomes the ideal choice when needing to await an external response during a flow's operation.

In contrast, other options such as Flow Input and Flow Output serve different roles. Flow Input is primarily used for gathering data or parameters when a flow is initiated. Flow Output pertains to sending information out from the flow but does not wait for an external response. Flow Notify is used to send notifications but doesn't incorporate waiting functionality. Thus, in the context of waiting for external responses, Flow Pause stands out as the appropriate action.