Final answer:
The moon that is tidally locked and experiences significant tidal heating due to its massive planet's gravitational pull is Europa. Europa has a subsurface ocean maintained in liquid form by the heat generated from the gravitational interactions with Jupiter.
Step-by-step explanation:
The student's question refers to a moon that is tidally locked to its planet, experiencing tidal forces that cause it to have permanent tidal bulges that always point toward and away from the planet. Among the options provided, Europa is known to experience significant gravitational interactions with Jupiter, leading to tidal heating effects similar to those described in the question. This squeezing and stretching generate enough heat to maintain a subsurface ocean in liquid form. While other moons like Ganymede, Callisto, Triton, and Enceladus also have interesting tidal interactions, it is Europa, which orbits closer to Jupiter, that is most famous for being geologically active due to Jupiter's immense gravitational field creating pronounced tidal forces. These tidal forces are crucial for the potential habitability of such moons, as they may allow for liquid water beneath their surfaces, making them subjects of Astro biological interest.