Hydrogen because it only has one valence electron I believe.
Answer:
Villi
Explanation:
In the small intestine, villi are found present. These villi which appear like a finger-like tissue structure are about 0.5–1.6mm in length in human beings.They have mucosal cells that help in absorption of nutrients. A villus has several microvilli, which increases the surface area of the intestinal wall for faster absorption of nutrients.
