In fighting a fire in a fuel tank, the FIRST action you should attempt is to __________.

Correct Answer: Option A — secure all sources of fresh air to the tank

Fire requires oxygen to sustain combustion. By securing all sources of fresh air, such as vents and dampers, you starve the fire of oxygen. This is the most critical first step in fire suppression, as it prevents the fire from growing and facilitates easier extinguishment.