<prompt> Essential amino acid amongst the followingArginineLysineThreonineAll  <response>: Essential amino acids: These are the ones which are not synthesised by the body and must be taken in diet. They include valine, leucine, isoleucine, phenylalanine, threonine, tryptophan, methionine and lysine. For remembering the following formula is used--MATT VIL PHLY.Ref: Textbook of medical biochemistry, MN Chatterji, 8th edition, page no: 80 