Villi and Microvilli That Are Associated with the Luminal Surface

Villi and microvilli that are associated with the luminal surface of the intestinal epithelium are important in that they

A) contain stratified layered) epithelial cells for protection against pathogens entering with food.
B) transport substances from the epithelial cells into the circulatory system.
C) contain cilia that facilitate movement of the contents of the alimentary canal toward the anus.
D) increase the surface area available for absorption.