Answer:
A
Step-by-step explanation:
In a simple perspective, an ion of an element is an element +-
amount of electrons.
We know that electrons have atomic mass, so we can mark off D
We know that with more or fewer electrons, the electron configuration would change
However, the number of protons won't change in the ion of an element, this is because an ion is only the change in electrons, not protons or neutrons (the particles that make up a nucleus of an atom)