Which is not true for arginine?

Which of the following molecules forms a Zwitter ion?

Total number of essential amino acids among the given list of amino acids is . . . .
Arginine,Phenylalanine,Aspartic acid,Cysteine,Histidine,Valine,Proline

Glycine may be classed as all of the following except

Identify the incorrect statement about the tertiary structure of proteins.

Which of the statements about "Denaturation" given below are correct?
$A$. Denaturation of proteins causes loss of secondary and tertiary structures of the protein
$B$. Denaturation leads to the conversion of double strand of $DNA$ into single strand
$C$. Denaturation affects primary structure which gets distorted