The cells lining the small intestine have projections into the lumen of the intestine. These projections, combined with the highly folded layering of cells lining the lumen, function to

A) slow the nerve impulses that trigger peristalsis.
B) increase the surface area for nutrient absorption.
C) facilitate countercurrent exchange.
D) decrease the reabsorption of water.
E) increase the rate of peristalsis.