What system satisfies the operational need of the Navy and Marine Corps by providing a commercial off-the-shelf engine installation and removal capability?

The correct answer is the Engine Installation and Removal Vehicle (EIRV). This system is designed specifically to meet the operational needs of the Navy and Marine Corps by offering a streamlined solution for the installation and removal of engines in a more efficient manner. The EIRV utilizes commercial off-the-shelf technology, which allows for quicker integration and adaptability to existing processes, thereby enhancing maintenance capabilities.

In contrast, the other options do not provide the same level of targeted engine handling efficiency. For example, ECM refers to Engine Control Module, which is essential for controlling engine performance but does not address the physical installation or removal of the engine. MWR stands for Morale, Welfare, and Recreation, which is focused on programs and services for personnel rather than operational capabilities. RMS stands for Reliability, Maintainability, and Supportability, which encompasses broader aspects of systems engineering and lifecycle support but lacks the specific functionality related to engine installation and removal that the EIRV provides.