What must be done to activate a Water Fire Extinguisher?

To activate a Water Fire Extinguisher, turning the cylinder clockwise is the correct action because this action effectively opens the valve that allows water to flow through the extinguisher. This mechanism is designed to ensure that the extinguisher is safe and not activated accidentally. Once the valve is opened with a clockwise turn, the user can then direct the water towards the fire.

The other options do not correspond to the proper operation of a water fire extinguisher. Pulling the lever, pressing a button, or removing the hose may apply to other types of extinguishers or machinery but do not activate a water fire extinguisher, leading to potential confusion if someone is not familiar with the specific procedures required for different types of extinguishers. Understanding the correct activation procedure is crucial for effective fire response.