What type of squadron is composed of air transportation and aircraft maintenance personnel serving as an en-route station?

The correct answer is the Air Mobility Squadron. This type of squadron focuses on the rapid deployment and movement of personnel and cargo through airlift capabilities, ensuring that operations can continue seamlessly at en-route stations. They are specifically designed to support missions by providing essential air transportation services, which includes managing aircraft loading and unloading, maintaining aircraft readiness, and coordinating logistical support.

The role of the Air Mobility Squadron is critical during military operations where swift and effective transport is necessary to maintain operational tempo and support mission objectives. By being stationed at en-route locations, they ensure that aircraft and personnel are promptly prepared for immediate missions, reflecting their purpose in the overarching air transportation strategy.

In contrast, other types of squadrons, such as the Aerial Port Squadron, are more specialized in ground handling operations at air terminals rather than offering comprehensive en-route support, while Logistics Readiness Squadrons primarily focus on sustainment processes and supply chain logistics. Contingency Response Groups contain elements for rapid response operations but are not strictly dedicated to air transportation, making the Air Mobility Squadron the most fitting choice for the defined purpose in the question.