Which of the following natural amino acid is optically inactive?

Concept-
-All proteins are polymers of α-amino acids.
-Amino acids contain amino (–NH2 ) and carboxyl (–COOH) functional groups.
-Depending upon the relative position of the amino group with respect to a carboxyl group, the amino acids can be classified as α, β, γ, δ, and so on.
-Only α-amino acids are obtained on hydrolysis of proteins.
-They may contain other functional groups also.
Explanation-
-Glycine is an amino acid that has a single hydrogen atom as its side chain.
-An optically inactive substance is a substance that does not have optical activity (a substance that does not rotate the plane of plane-polarized light).
-Almost all the natural amino acids except glycine are optically inactive because glycine does not have a chiral carbon in its structure.

🔴Additional Information:
Alanine
-It is a non-essential amino acid.
-Alanine is an α-amino acid that is consumed in the biosynthesis of proteins
Valine
-Valine is an aliphatic and extremely hydrophobic essential amino acid in humans related to leucine.
-Valine is found in many proteins, mostly in the interior of globular proteins helping to determine the three-dimensional structure.
Aspartic acid
-Aspartic acid is a non-essential amino acid in humans.
It has codons GAC and GAU.