What should a pilot do after receiving an "ATC Clearance"?

The appropriate action a pilot should take after receiving an "ATC Clearance" is to prepare for the authorized operation under Instrument Flight Rules (IFR). This means that the pilot needs to review and understand the clearance, which includes the assigned route, any specified altitude, departure procedures, and any instructions regarding communication or coordination with air traffic control.

This preparation is crucial as it ensures that the pilot is fully aware of what is expected for the flight, allowing for smoother operations and increased safety. The IFR clearance acts as a guiding document for the flight, outlining the parameters within which the aircraft is expected to operate. A thorough understanding of the clearance helps the pilot plan for takeoff and en route operations effectively.

While the other options might suggest varying levels of caution or verification, they do not align with accepted procedures following the receipt of an ATC clearance. Taking immediate action or delaying without a valid reason could introduce risks or violate established protocols for safe aviation practices. Therefore, preparing for the authorized operation under IFR is the most appropriate and safe course of action following the receipt of ATC clearance.