Osmosis Drives Water Inflow, Active Transport Accumulates Ions

Steps:

• Water enters root hairs by osmosis, moving from higher concentration in soil to lower in root.
• Root cells maintain lower water potential inside via solutes, creating inflow gradient.
• Ions enter against their gradient via active transport, using ATP to reach higher concentrations in root.
• Thus, root has lower water and higher ion concentrations than soil.

Why A is correct:

• Osmosis requires lower water concentration in root for net inflow; active transport pumps ions to higher levels inside, per diffusion and energy principles.

Why the others are wrong:

• B: Higher water in root blocks osmosis inflow.
• C: Higher water in root blocks osmosis; lower ions prevent active accumulation.
• D: Lower water in root is correct for osmosis, but lower ions contradict active transport uptake.

Final answer: A