I have a 4 amino acid peptide of unknown sequence with a curious titration profile around pH = 6. If Iknow that the peptide N-terminus has a pKa = 9, C-terminus pKa = 3, and an obvious titration point at pH= 10.5, what amino acid could likely generate a strange titration profile at pH 6 in this peptide?a. Cysteineb. Tyrosinec. Histidined. Arginine