Final answer:
The nucleus of an atom contains protons and neutrons, collectively known as nucleons. Option D is correct.
Step-by-step explanation:
The subatomic particles found in the nucleus of an atom are protons and neutrons. These particles are collectively called nucleons. While protons are positively charged, neutrons carry no charge and are neutral.
Electrons are not found in the nucleus; they are located in the electron cloud surrounding the nucleus. Neutrinos are not a component of the atomic nucleus either. Therefore, the correct answer to which subatomic particles you would find in the nucleus of an atom is d. Both neutrons and protons.
Atoms that vary in the number of neutrons they have in their nuclei are called isotopes. Protons and neutrons have very similar masses, with the neutron being slightly more massive; however, both are much more massive than electrons, with most of the atom's mass concentrated in the nucleus.
Protons are positively charged, while neutrons are neutral. Electrons, much less massive than nucleons, orbit the nucleus and are not found within it.