What is the mechanism that is essential for the absorption of monosaccharides?
Correct Answer: B
Rationale: Active transport is the mechanism essential for the absorption of monosaccharides in the intestine. This process requires energy to move molecules against their concentration gradient, allowing for the absorption of monosaccharides efficiently. Phosphorylation, the process of adding a phosphate group to a molecule, is not directly involved in the absorption of monosaccharides. Passive diffusion, a process that does not require energy, is not the primary mechanism for absorbing monosaccharides due to their large size. Facilitated diffusion, a type of passive transport that involves carrier proteins, is not the primary mechanism for monosaccharide absorption, as monosaccharides require active transport for efficient absorption.