The correct answer is A. Electron
Explanation:
The model of this atom depicts the nucleus of this in the center of the model, this section of the atom contains sub-particles known as protons and neutrons. Moreover, in the atom, the nucleus is surrounded by three sub-particles that orbit or move around the nucleus. These sub-particles are the electrons; these differ from other sub-particles because they have a negative charge and they are not part of the nucleus. Also, these move around the nucleus is orbits, although they move similarly to waves. According to this, the correct answer is A.
