Rock Cycle and Soil Formation

What is the parent rock?

Which of the following best describes parent rock?

Responses

crushed gravel added to depleted soil to provide nutrients
crushed gravel added to depleted soil to provide nutrients

the lowest layer of the soil horizon, containing little or no organic matter
the lowest layer of the soil horizon, containing little or no organic matter

high-nutrient igneous rock like obsidian, extruded from the earth’s magma
high-nutrient igneous rock like obsidian, extruded from the earth’s magma

the primary stone sheet from which a boulder or stone originated
the primary stone sheet from which a boulder or stone originated

Answer:

The primary stone sheet from which a boulder or stone originated.

Parent rock, also known as bedrock, refers to the original rock from which soil is formed through the process of weathering and erosion. This process breaks down the parent rock into smaller particles that eventually make up the soil. The primary stone sheet from which a boulder or stone originated accurately describes this concept by mentioning that parent rock is the primary stone sheet from which stones or boulders originated, serving as the source material for soil formation.