The process of stabilizing two vehicles that must come to rest on top of each other is:

The term that describes the process of stabilizing two vehicles that have come to rest on top of each other is "Marrying." This process is crucial in vehicle rescue situations involving stacked vehicles, as it ensures that both vehicles are secure and won’t shift during rescue operations. Marrying involves creating a connection between the two vehicles, often using mechanical devices like straps or chains, to provide stability and prevent further movement. This practice is essential for the safety of both the rescuers and any potential victims still inside the vehicles.

The other options do not accurately represent this specific process. Anchoring generally refers to securing a vehicle or object to a stable base to prevent movement but does not specifically address the scenario of two vehicles resting on each other. Stabilizing is a more general term that refers to making any object stable and could apply in a broader sense, but does not capture the unique intricacies of the marrying technique. Basing is not commonly used in this context and does not refer to vehicle stabilization at all.