Which statement correctly the statement ?
Except for glycine, which is achiral, all the amino acids present in proteins....

Options

A. are chiral, but racemic
B. have the L configuration at their `alpha` carbon
C. have the R configuration at their `alpha` carbon
D. have the S configuration at their `alpha` carbon

Answer

B

Explanation

Amino acids which combine into peptide chains to form the building blocks of a rest array of proteins are all L-stereoisomers (left handed)
`"Glycine" " " NH_(2)-CH_(2)-COOH`
`"L-Amino acid" " " NH_(2)-underset(R)underset(|)(CH)-COOH`