Final answer:
Benzoic acid (C6H5COOH) is most likely to exhibit a significant change in solubility due to alterations in pH because it is a weak acid with a conjugate base that can be protonated.
Step-by-step explanation:
Among the compounds listed, benzoic acid (C6H5COOH) is most likely to exhibit a significant change in solubility due to alterations in pH. This is because benzoic acid is a weak acid, and its conjugate base (the benzoate ion) can become protonated in acidic conditions, affecting its solubility. Sodium chloride (NaCl) and sucrose (C12H22O11) do not have this behavior because NaCl is the salt of a strong acid and a strong base, and sucrose is a non-electrolyte. Hydrochloric acid (HCl) is a strong acid and fully ionizes in solution, thus pH changes do not greatly affect its solubility.