What type of hose lay allows the engine company to establish a water supply without outside assistance?

The forward lay is the correct choice because it is a method where the engine company connects directly to a water source, such as a hydrant, while simultaneously laying hose to the scene of the emergency. This technique allows the firefighters to establish a reliable water supply right from the beginning without needing assistance from other units or companies.

During a forward lay, the engine drives past the fire location, establishes the supply line to the water source, and then can immediately begin operations, such as fighting the fire or protecting exposures, once arriving at the scene. This method enhances operational efficiency and reduces response time for extinguishing the fire since water is available at the start of firefighting operations.

In contrast, other hose lays, such as reverse, split, and lateral, have different applications and may involve either more complex setups or require assistance from additional units or crews to effectively manage the water supply, which is not the goal when establishing an independent water supply quickly.