Question

the atomic mass of an atom equals the sum of the masses of the ____.
○ protons and electrons
○ electrons and neutrons
○ protons and neutrons
○ none of the above

Explanation:

To determine the correct option, we recall the structure of an atom. The atomic mass of an atom is primarily determined by the sum of the masses of protons and neutrons, as electrons have a negligible mass compared to protons and neutrons.

Answer:

C. protons and neutrons