What action should be taken if the cockpit pressurization light illuminates?

When the cockpit pressurization light illuminates, it indicates a potential issue with the aircraft's pressurization system that could compromise safety. The appropriate action in this scenario is to perform the emergency depressurization checklist. This checklist outlines critical steps to manage cabin pressure and ensures that the crew is prepared for any situation that may arise from a sudden loss of cabin pressure.

Performing the emergency depressurization checklist helps the pilot understand the specific nature of the issue, assess the cabin altitude, and take necessary precautions to protect the crew and passengers. This may include actions like donning oxygen masks if needed, initiating a controlled descent to a lower altitude where oxygen is sufficient, and preparing for an emergency landing if the circumstances warrant it.

The other options do not adequately address the urgency and potential risks associated with cabin depressurization. Continuing flight as normal overlooks the serious implications of pressurization loss, while gradual descent without following the checklist might not ensure passenger safety or proper aircraft handling. Checking fuel levels, while important for overall operations, does not relate directly to the immediate concern posed by the illumination of the cockpit pressurization light.