Which two subatomic particles each have a mass of approximately one atomic mass unit?

• A. Electron and positron
• B. Neutron and electron
• C. Proton and neutron
• D. Electron and proton

Answer: (C)

Verified step by step guidance

1. Recall the three main subatomic particles: protons, neutrons, and electrons.
2. Understand that the atomic mass unit (amu) is approximately the mass of one proton or one neutron.
3. Note that electrons have a much smaller mass compared to protons and neutrons, about 1/1836 of an amu.
4. Recognize that positrons are the antimatter counterparts of electrons and have the same small mass as electrons.
5. Conclude that the two subatomic particles with masses close to one atomic mass unit are the proton and the neutron.