Sources: Uworld Question Bank, QID 403183
The question can be answered using the passage and process of elimination. However, because it specifically requires knowledge of the three-letter abbreviations for amino acids, I believe a tag is needed.
The question:
Which of the following titration curves corresponds to the amino acid found in peak 17 of the chromatogram?
(The question then provides four titration curves, each with two or three pKa values.)
Peak 17 in the graph is depicted with the three-letter abbreviation Lys, meaning Lysine.
Next, you must refer to the provided pKa chart, which lists the full names of the amino acids. This is why I tagged this card — you need to know the three-letter abbreviation to correctly identify the amino acid and match it to the side chain pKa values.