Which of the following statements are false regarding the nature of amino acids?
A. The acidity and neutrality of amino acids is based on number of amino and carboxyl groups.
B. Both NH₂ and COOH groups of amino acids show ionizable nature.
C. In solutions of different pH, the structure of amino acids does not change.
D. The amino acids have amino group and aldehyde group as substituents on the same carbon.