Answer:
C.) protons, neutrons, and electrons, only
Step-by-step explanation:
According to the modern atomic theory, we can distinguish 2 parts in an atom:
- The nucleus, where is the majority of the mass of the atom, that is, protons and neutrons
- The external shell, where are the electrons.
In a neutral atom, there are the same number of protons (positive charges) as electrons (negative charges).