Which two bases depend on a dovetail cut into the receiver?

The correct answer highlights two bases that rely on a dovetail cut in the receiver, specifically the Ruger and Rimfire models. Dovetail cuts are designed into the receiver to accommodate mounts for scopes or sights. This design allows for a secure attachment point that provides stability and repeatability when aiming and firing, which enhances accuracy.

Ruger firearms, particularly those meant for rimfire cartridges, frequently utilize this dovetail system in their receivers. This allows shooters to easily install and adjust optics to suit their preferences for optimal performance.

In contrast, while other options may indeed feature different mounting systems—some using screw holes or integral mounts—they do not employ the dovetail design as standard in the same way that Ruger and Rimfire firearms do. Thus, the emphasis on the dovetail cut as a mounting basis is integral to the function and utility of the specified firearms.