C. H₃O⁺ is a Bronsted Lowry base.
Explanation:
Any substance that accepts hydrogen ions or (H⁺) ions or protons during any chemical reaction is termed as a Bronsted Lowry base.
Here HCl donates a proton so it is not a Bronsted Lowry base.
HCO is also not a Bronsted Lowry base.
H₃O⁺ is a Bronsted Lowry base because it accepts H⁺ ion from one of its reactant.
H₃PO₄ is also not a Bronsted Lowry base.
So option C. H₃O⁺ is a Bronsted Lowry base.
