An example of a process that involves osmosis is the

Step 1: Analyze the question We need the process that involves osmosis. Osmosis is the movement of water molecules from a region of high water potential (dilute solution) to a region of low water potential (concentrated solution) through a partially permeable (selectively permeable) membrane.

Step 2: Explain the concept Osmosis applies only to the movement of water. Movement of dissolved solutes such as glucose and amino acids usually happens by diffusion or active transport, not osmosis.

Step 3: Check each option

• A. Movement of water from root hairs into cortical cells: Soil water is dilute, so it has a high water potential. The cell sap of the root hair is more concentrated, and water moves from the root hair cell into the cortical cells along a water potential gradient. This is osmosis. ✔
• B. Reabsorption of food nutrients from the kidney into blood capillaries: This involves nutrients (solutes) such as glucose, which are reabsorbed mainly by active transport. ✘
• C. Translocation of starch from leaves: Starch is insoluble and is not translocated. Sugars (sucrose) are carried in the phloem by active, pressure-flow processes. ✘
• D. Movement of digested food from ileum into blood capillaries: Digested food is absorbed by diffusion and active transport. ✘

Step 4: Answer The correct option is A.

Tip: When you see "osmosis" in an exam, look for the option that involves only water moving across a membrane. Water uptake by root hairs is the classic example. If the option mentions food, nutrients, or sugars, it is probably not osmosis.