ILL MARK AS BRAINLIEST:) Tell me with your own words;

How to write a formula of an ionic and covalent compound.
*Include metals with more than one charge.
*Include polyatomic ions

Explanation:

The prefix poly- means many, so a polyatomic ion is an ion that contains more than one atom. This differentiates polyatomic ions from monatomic ions, which contain only one atom. Examples of monatomic ions include \text{Na}^+Na+start text, N, a, end text, start superscript, plus, end superscript, \text{Fe}^{3+}Fe3+start text, F, e, end text, start superscript, 3, plus, end superscript, \text{Cl}^-Cl−start text, C, l, end text, start superscript, minus, end superscript, the conventions for naming ionic compounds and writing their chemical formulas.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.