What is attached to the suction hose connected to the raw water pump to prevent the intake of damaging objects?

The correct answer is a strainer, which is specifically designed to be attached to the suction hose of a raw water pump. Its primary purpose is to filter out debris and larger particles from the water before it enters the pump. This is crucial because allowing foreign objects to enter the pump system could lead to damage, reduced efficiency, or even pump failure.

A strainer works by employing a mesh that captures any solid material while permitting the flow of water to continue, ensuring that the system operates smoothly. They are typically constructed from materials that can withstand the elements and are easy to clean or replace when necessary, making them a vital component in maintaining the integrity and longevity of water systems.

In contrast, a float would generally serve a different purpose, typically related to maintaining levels in a tank or preventing overflow. A gate valve is used to control the flow of water but does not serve the function of filtering out particles. A distribution pump is responsible for moving the water through the system rather than protecting it from contaminants. Thus, the strainer is the correct choice for protecting the raw water pump intake from damaging materials.