A student is investigating the water retention properties of three different soil types, Q, R, and S, using the experimental setup shown in Fig. 21. The table below shows the amount of water that drai

21 to determine the water retention of each soil type.
The diagram shows the amount of water collected after draining through soils Q, R, and S. The less water collected, the more water the soil retained.

• Soil Q allowed the least water to drain through (smallest amount in the collection tube), meaning it retained the most water.
• Soil R allowed an intermediate amount of water to drain through, meaning it retained an intermediate amount of water.
• Soil S allowed the most water to drain through (largest amount in the collection tube), meaning it retained the least water.

• A. Soil Q retained more water than soil R. (Correct, as Q retained the most water, and R retained less than Q).
• B. Soil S retained the highest amount of water. (Incorrect, S retained the least amount of water).
• C. Soil Q retained the smallest amount of water. (Incorrect, Q retained the highest amount of water).

The correct statement is A.
The final answer is $\boxed{\text{A}}$

21 to known soil properties.

• Soil Q retained the most water. Soils with very small particles, like clay, have high water retention.
• Soil S retained the least water. Soils with large particles, like sand, have low water retention and good drainage.
• Soil R retained an intermediate amount of water. Loam soil, a mixture, has moderate water retention.

• Soil Q, with the highest water retention, is Clay soil.
• Soil S, with the lowest water retention, is Sand soil.
• Soil R, with intermediate water retention, is Loam soil.

Therefore:

• Q = Clay soil
• R = Loam soil
• S = Sand soil