Final answer:
Benching systems cannot be used in Type C soils, as they are highly cohesive and do not require additional support. They can, however, be used in Type A and Type B soils, as well as in solid rock.
Step-by-step explanation:
In type C soils, also known as highly cohesive soils, benching systems cannot be used. Type C soils have cohesion and exhibit a high degree of stability when excavated, making them strong enough to stand on their own without additional support. Therefore, benching systems are not necessary in these types of soils.
On the other hand, benching systems are commonly used in Type A and Type B soils, as well as in solid rock. Type A soils are cohesive soils with high strength, while Type B soils are cohesive soils with medium strength. Solid rock is a stable material that is capable of supporting the weight of benching systems.