The correct answer is option 3, neither I nor II.

Let`s break down each statement:

I. Digestion of the milk protein, casein is initiated in the duodenum with its coagulation.

This statement is incorrect. Casein, a milk protein, is actually coagulated in the stomach, not in the duodenum. The stomach secretes an enzyme called rennin, which coagulates casein and forms a solid curd. The coagulated casein is then broken down further in the small intestine, specifically in the duodenum.

II. Trypsin hydrolyzes casein into paracasein and whey proteins.

This statement is also incorrect. Trypsin is an enzyme produced by the pancreas and secreted into the small intestine. It primarily hydrolyzes proteins into smaller peptides but does not specifically hydrolyze casein into paracasein and whey proteins. In fact, the enzyme chymotrypsin is responsible for breaking down casein into its constituent peptides.

Therefore, neither statement I nor statement II is correct, and the correct answer is option 3, neither I nor II.