Biology

Correct Option: B) The presence of villi and microvilli

Explanation: Villi are finger-like projections on the inner surface of the small intestine, and microvilli are tiny projections on the surface of epithelial cells on the villi.
Together, they greatly increase the surface area of the small intestine, allowing for more efficient absorption of nutrients.

Incorrect Options:

A) The smooth lining of the small intestine:
The smooth lining of the small intestine aids in peristalsis (the movement of food), but it ...