Answer: Option (A) is the correct answer.
Explanation:
When a neutral atom loses an electron then it acquires a negative charge and if a neutral atom gains an electron then it acquires a positive charge. Hence, an ion is formed in both the cases.
For example, sodium on losing an electron become [tex]Na^{+}[/tex] ion.
An isotope is defined as the specie which contains same number of protons but different number of neutrons.
For example, [tex]^{14}_{7}N[/tex] and [tex]^{15}_{7}N[/tex] are isotopes.
A molecule is defined as a substance that contains chemically combined two or more number of atoms of an element.
For example, [tex]Cl_{2}[/tex] is a molecule.
Whereas a compound is defined as a substance in which different atoms of different elements chemically combine together in a fixed ratio by mass.
For example, [tex]H_{2}O[/tex] is a compound.
Thus, we can conclude that an ion is an electrically charged atom.
