Which process describes the breakdown of rocks at Earth’s surface into smaller pieces?

Which process describes the breakdown of rocks at Earth’s surface into smaller pieces?

• A. Weathering
• B. Erosion
• C. Melting
• D. Sedimentation

Answer: (A)

Rocks breaking down into smaller pieces at Earth’s surface is weathering. This happens through physical forces like freezing and thawing, abrasion, or chemical reactions with water and air, which gradually reduce rocks to smaller fragments and sometimes form soil in place. Erosion, by contrast, is the movement of those pieces away from their original location, not the initial breakdown. Melting would turn rock into liquid magma, a change of state rather than a surface breakdown. Sedimentation describes the deposition of particles after they’ve been transported, not how rocks first become smaller pieces.

Rocks breaking down into smaller pieces at Earth’s surface is weathering. This happens through physical forces like freezing and thawing, abrasion, or chemical reactions with water and air, which gradually reduce rocks to smaller fragments and sometimes form soil in place. Erosion, by contrast, is the movement of those pieces away from their original location, not the initial breakdown. Melting would turn rock into liquid magma, a change of state rather than a surface breakdown. Sedimentation describes the deposition of particles after they’ve been transported, not how rocks first become smaller pieces.