Pick up the correct statement from the following: A. Adding 5% to 6% of moisture content by weight, increases the volume of dry sand from 18% to 38% B. The bulking of fine sand is more than that of coarse sand C. If the percentage content of moisture exceeds 10%, increase in bulk of sand starts increasing D. All the above

The correct answer is D. All the above.

When water is added to sand, the individual grains of sand become coated with a thin layer of water. This layer of water prevents the grains of sand from touching each other as closely, which increases the volume of the sand. The amount of increase in volume depends on the amount of water added. Adding 5% to 6% of moisture content by weight, increases the volume of dry sand from 18% to 38%.

The amount of bulking is also affected by the size of the sand grains.

Fine sand has a greater surface area than coarse sand, so it takes up more space when it is coated with water. This is why fine sand has a greater bulking effect than coarse sand.

If the percentage content of moisture exceeds 10%, the increase in

bulk of sand starts increasing. This is because the water molecules start to form bridges between the sand grains, which further increases the volume of the sand.

Therefore, all of the statements in the question are correct.