Final answer:
Glycine is the amino acid that is most likely to be soluble in benzene.
Step-by-step explanation:
Amino acids are classified into several categories based on their solubility properties. Hydrophobic amino acids, such as Alanine, Phenylalanine, Leucine, and other similar amino acids with nonpolar R groups, are generally insoluble in water and benzene. On the other hand, hydrophilic amino acids, like Glycine, are soluble in water but not necessarily soluble in benzene. Therefore, out of the given options, Glycine would be the amino acid that is most likely to be soluble in benzene.