The non-protein part co-factor includes organic & metallic organic molecule and sometimes _.

Explanation

OPTION A: Vitamins are considered essential nutrients that are required in small amounts in the diet and are not classified as cofactors because they don't function as catalysts in enzymes and metabolic reactions, unlike organic and metallic organic molecules which are considered non-protein cofactors that help enzymes carry out their functions.OPTION B: DNA is not considered a non-protein part of a cofactor. It is the genetic material that contains the instructions for the development, functioning, and reproduction of all living organisms.OPTION C: The coenzyme is a type of cofactor that helps in the reaction completion by enhancing the enzyme activity. It is mostly present in enzyme-catalyzed reactions and is a non-protein part of the enzyme. The cofactors that are composed of organic constituents are called a coenzyme. They function as a catalyst in different reactions. They mostly contain vitamins as their essential components. For example, the coenzyme nicotinamide adenine nucleotide (NAD) and NADP contain the vitamin niacin in them.OPTION D: This option is not correct.