Questions: Which correctly lists the three parts of soil that are classified by their particle size? bedrock, humus, and clay clay, bedrock, and silt humus, sand, and clay sand, clay, and silt

The answer is the fourth one: sand, clay, and silt.

Explanation for each option:

1. Bedrock, humus, and clay: This option is incorrect because bedrock and humus are not classified by particle size. Bedrock is the solid rock layer beneath the soil, and humus is organic matter in the soil.

2. Clay, bedrock, and silt: This option is incorrect because bedrock is not classified by particle size. While clay and silt are soil particles, bedrock is not.

3. Humus, sand, and clay: This option is incorrect because humus is not classified by particle size. Humus is organic material, whereas sand and clay are soil particles.

4. Sand, clay, and silt: This option is correct because sand, clay, and silt are the three main soil particles classified by their size. Sand has the largest particles, silt has medium-sized particles, and clay has the smallest particles.

In summary, the correct classification of soil particles by size is sand, clay, and silt.