i have no idea figure it out yourself
I think is D,,,,,,,,,,,,,,,,,
C. Serving as a Shock absorber and cleaning agent
The answer to this question is histidine. Histidine i<span>s an </span>α-amino acid<span> involved in the biosynthesis of </span>proteins. The structure of histidine includes<span> an </span>α-amino acid<span>, a </span>carboxylic acid group<span>, and an </span>imidazole<span> side chain. Histidine was initially thought to be </span>essential<span> only for infants; however, it has since been found to be essential for adults too.</span>