Concept:Mechanical weathering breaks rocks into smaller pieces by physical action.
The process described is the peeling of outer layers from a rounded boulder.
This is known as exfoliation or onion weathering.
Explanation:During mechanical weathering, rounded boulders are heated by the sun during the day and cool down at night.
Repeated heating and cooling makes the outer layers expand and contract differently from the inner rock.
As a result, the surface layers gradually crack and peel off in curved sheets.
This peeling action is like removing layers of an onion.
The process is not simply rock fragmentation, because fragmentation means general breaking into fragments.
Solifluction is the slow flow of waterlogged soil, not rock peeling.
Weathering is the broad general term for all rock breakdown.
Therefore, the specific name for the peeling of surface layers is exfoliation.
Answer:C. Exfoliation.