The correct answer is C. Osmosis.
Osmosis is the movement of water molecules from an area of high water concentration to an area of low water concentration. In plant epidermal cells, the water concentration is higher outside the cell than inside the cell. This is because the cell membrane is semi-permeable, which means that it allows water molecules to pass through, but not other molecules. As a result, water molecules move from the outside of the cell to the inside of the cell, causing the cell to swell.
Active transport is the movement of molecules against a concentration gradient, which requires energy. Translocation is the movement of substances within a plant, such as sugars and minerals.
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