Concept:Osmosis is the movement of water molecules from a region of higher water concentration to a region of lower water concentration through a selectively permeable membrane.
Explanation:Water from the soil enters the root hairs by osmosis because the cell sap of root hairs has a lower water concentration than the soil water.
From the root hairs, water moves into the cortical cells, which also have a lower water concentration than the root hair cells.
This creates a continuous osmotic gradient that allows water to pass from cell to cell through the root.
Option B involves active transport of nutrients, not osmosis.
Option C, translocation of starch, occurs through phloem tissue and is not osmosis.
Option D, absorption of digested food in the ileum, mainly involves diffusion and active transport.
Therefore, only the movement of water from root hairs into cortical cells is a direct example of osmosis.
Answer:A. movement of water from root hairs into cortical cell