A basic amino acid is likely to contain which of the following functional groups in its R group?

Identify the functional groups associated with basic amino acids: Basic amino acids, such as lysine, arginine, and histidine, have R groups that contain functional groups capable of accepting protons (H⁺), making them positively charged at physiological pH. The amino group ( $-N_{\mathrm{H}}2$) is a common functional group in the R group of basic amino acids.

Compare the given options: Hydroxyl group ( $-{\mathrm{OH}}_{}$), sulfhydryl group ( $-{\mathrm{SH}}_{}$), and carboxyl group ( $-{\mathrm{COOH}}_{}$) are not characteristic of basic amino acids' R groups. The amino group ( $-N_{\mathrm{H}}2$) is the correct functional group associated with basic amino acids.