Which choice completes the text so that it conforms to the convention…

Source Texts

Text

In a chemical equation, converting between the mass of the reactants and the mass of the product requires knowing each component's molar mass, a quantification of the average mass of the atoms in a compound. The gaseous _____ has a molar mass of 48.00 g/mol.

Which choice completes the text so that it conforms to the conventions of Standard English?

compound ozone (O

_{3}

compound, ozone (O

_{3}

)

compound ozone (O

_{3}

)

compound, ozone (O

_{3}