Answer: The correct answer is Option D.
Explanation:
There are 3 subatomic particles that are present in an atom. They are: protons, electrons and neutrons.
- Protons carry positive charge and are found inside the nucleus of an atom.
- Electrons carry negative charge and are found around the nucleus in the orbits.
- Neutrons does not carry any charge and are found inside the nucleus of an atom.
Atomic mass is defined as the sum of number of protons and neutrons that are present in an atom.
Atomic mass = Number of protons + Number of neutrons
Hence, the correct answer is neutrons.
