Answer:
Biocatalyst or enzyme
Explanation:
The Lactose is a disaccharide sugar or carbohydrate found in the milk and the milk products.
The breakdown of the lactase is very difficult but the presence of a protein molecule called lactase-phlorizin hydrolase or lactase makes the breakdown of the lactose int galactose and glucose easy.
Such protein molecules which increase the rate of reaction are called enzymes and since the breakdown of lactose is a biological process, therefore, the enzymes are also known as the enzymes or the biocatalyst they increase the speed of the reaction.
Thus, Biocatalyst or enzyme is the correct answer.