What is the principal functional role of brush border enzymes in the small intestine?

They complete the final steps of carbohydrate and peptide digestion at the enterocyte surface so products are small enough (monosaccharides, di/tripeptides, amino acids) for immediate absorption into epithelial cells

They secrete bile and pancreatic enzymes directly into the lumen to emulsify fats before pancreatic secretions arrive

They pump iron and calcium into the lumen to increase mineral concentrations and slow absorption

They primarily synthesize large complex carbohydrates de novo to be exported into the bloodstream