Which of the following particles demonstrates wave-particle duality?

Wave-particle duality is a fundamental concept in quantum mechanics that describes how particles, such as electrons, can exhibit both wave-like and particle-like behavior. This principle is most clearly demonstrated in experiments like the double-slit experiment, where electrons create an interference pattern typical of waves when not observed but display particle-like behavior when measured.

Electrons have a relatively small mass and are confined to tiny scales, allowing their wave-like properties to become apparent. Their behavior can be described by wave functions, which provide probabilities of finding an electron in a given location, embodying both aspects of being a particle that can exist in a defined position and a wave that spreads out over space.

In contrast, while protons, neutrons, and ions are also subject to quantum mechanics, their larger mass and other properties demonstrate wave-particle duality less prominently compared to electrons. Thus, among the given options, electrons best embody the concept of wave-particle duality, showcasing the essential nature of subatomic particles in quantum physics.