The correct option is A Dehydration synthesis
Proteins are synthesized by joining together of amino acids. Amino acids are joined together by dehydration condensation reactions in which a water molecule is released when two amino acids react. One of the amino acids contributes a hydroxyl group from its carboxylic group and another amino acid contributes a proton from its amino group and one water molecule is removed leading to the formation of a peptide bond between amino acids.