What must a hose be capable of conducting from one end to the other?

The correct choice is that a hose must be capable of conducting gas from one end to the other. When dealing with CNG systems, the primary function of the hoses used is to safely convey compressed natural gas from one component of the system to another, such as from the storage tank to the engine. These hoses are specifically designed to withstand the pressures and chemical properties associated with natural gas.

In this context, while hoses can be used for various substances, including water or air, the critical requirement for CNG applications is their ability to handle gas under pressure. Hoses designed for gas transport are constructed from materials that prevent leaks and maintain integrity under high-pressure conditions typical of CNG systems. Understanding this fundamental aspect ensures the safety and efficiency of CNG fueling and storage systems.