Which of the following terms would refer to a chemical technique for manufacturing nanometerials?

The sol-gel process is a wet-chemical technique commonly used to synthesise a wide variety of nanomaterials. The sol-gel process is a wet-chemical technique widely used in the fields of materials science and ceramic engineering. Such methods are used primarily for the fabrication of materials (typically metal oxides) starting from a colloidal solution (sol) that acts as the precursor for an integrated network (or gel) of either discrete particles or network polymers.