Final answer:
The option that is not one of the four stages of terrestrial planet development is D. fusion of hydrogen to helium, as this is a process associated with stars, not planets. Differentiation, cratering, and slow surface evolution are stages that describe how a planet's interior and surface evolve.
Step-by-step explanation:
The formation and development of terrestrial planets involve several stages. The stages significant in shaping such planets are accretion, heating, differentiation, formation of a solid crust, and heavy cratering followed by extensive volcanic activity similar to mare-like volcanism found on our Moon.
Therefore, the option that is NOT a stage in the development of a terrestrial planet is D. fusion of hydrogen to helium. This process is a fundamental reaction that occurs in stars, including our Sun, not terrestrial planets. It's the process that powers a star, resulting in the release of energy and the formation of helium from hydrogen through nuclear fusion.
The other option given, such as differentiation, is the process where a planet's interior separates into layers of different compositions and densities, with heavier metals sinking to the core and lighter minerals forming the crust. Cratering is a stage where impacts from other celestial bodies create craters on the surface, and slow surface evolution involves geological and atmospheric changes over time that shape the planet's surface features.