Question

when a neutral atom gains or loses electrons, it becomes
more stable.
an isotope.
an ion.
less charged.

Explanation:

An ion is formed when a neutral atom gains or loses electrons. Gaining electrons makes it a negatively - charged anion, and losing electrons makes it a positively - charged cation. Isotopes are atoms of the same element with different numbers of neutrons. A neutral atom gaining or losing electrons does not necessarily make it more stable in all cases, and it definitely does not make it less charged.

Answer:

an ion.