2O represents two . . . . . . . . of oxygen. A. ions B. atoms C. molecules D. electrons

ions
atoms
molecules
electrons

The correct answer is C. molecules.

Oxygen is a diatomic molecule, meaning that it is made up of two oxygen atoms. The chemical formula for oxygen is O2. This means that two oxygen atoms are bonded together to form a molecule.

An ion is an atom or molecule that has a positive or negative charge. This is because it has gained or lost electrons.

An electron is a subatomic particle that has a negative charge. It is found in the outermost shell of an atom.

Therefore, the correct answer is C. molecules.