<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A medical student is studying digestive enzymes at the brush border of the duodenum. He isolates and inactivates an enzyme in the brush border that has a high affinity for the pancreatic proenzyme trypsinogen. When the enzyme is inactivated, trypsinogen is no longer converted to its active form. Which of the following is the most likely underlying mechanism of this enzyme?? A: Conjugation of ubiquitin to lysine residue, B: Phosphorylation of an amino acid side chain, C: Attachment of a carbohydrate to a side chain, D: Carboxylation of a glutamate residue, E: Cleavage of a propeptide from an N-terminus,  <response>: This is a question about digestive enzymes in the duodenum. It describes an experiment where a student isolates and inactivates an enzyme that converts trypsinogen to trypsin. When this enzyme is inactivated, trypsinogen can no longer be converted to trypsin. The question asks which mechanism is most likely responsible for the enzymes activity. Based on the information provided, it seems the enzyme cleavesremoves a propeptide from trypsinogen to activate it into trypsin. Of the answer choices provided, choice E Cleavage of a propeptide from an N-terminus best matches this hypothesized mechanism. The other choices describe different types of enzyme modifications that do not seem relevant based on the information provided.E: Cleavage of a propeptide from an N-terminus 