Final answer:
In dangerous type C soil, the angle of repose for sloping is less than 45 degrees to prevent collapse and ensure safety in construction zones.
Step-by-step explanation:
The angle of repose is the maximum angle at which a soil or any granular material can be piled without slumping. In the context of type C soil, which is considered the most hazardous within the construction industry due to its poor stability and high probability to collapse, the angle of repose is critical for ensuring the safety of sloping and excavation work.
When considering type C soil, the angle of repose for sloping falls into the first category, which is less than 45 degrees. This less steep angle helps to prevent material from cascading or sliding down, which can pose significant risks in a construction setting.