Electrons in which area of an atom are more difficult to move?

The correct answer is the valence ring (shell). In the structure of an atom, the valence shell contains the outermost electrons that are involved in chemical bonding. While these electrons are relatively less tightly bound to the nucleus compared to those in inner shells, they are still influenced by the atom's overall electron configuration.

However, when considering movement in terms of energy required to remove or affect these electrons, the context suggests that they are more difficult to move in comparison to electrons from the inner orbits. The inner electrons are generally more strongly attracted to the nucleus due to being closer and experiencing a stronger positive charge, meaning the valence electrons are, in fact, easier to manipulate in certain conditions.

It's also important to note that the nucleus is not where electrons reside; instead, it contains protons and neutrons. Thus, designing a question around electron mobility within the context of atomic structure will establish that the outermost electrons in the valence shell are pivotal in reactions and chemical interactions, representing a misinterpretation in the initial choice.