Consider the structure of an amino acid and its behavior in different pH environments. Amino acids possess both an amino group (-NH₂) and a carboxyl group (-COOH), which play crucial roles in their reactivity and structure. At physiological pH (approximately 7.4), many amino acids exist predominantly in their zwitterionic form, where the carboxyl group is deprotonated (-COO^-) while the amino group remains protonated (-NH₃⁺).

In contrast, at lower pH values, the solution becomes more acidic, leading to the protonation of the carboxyl group. At higher pH values, the deprotonation of the amino group occurs. Examine the following representations of an amino acid at three different pH levels: low (pH 3), physiological (pH 7.4), and high (pH 10). Which representation accurately depicts the amino acid at pH 10?