* Differential weathering is the process where different rocks or parts of a rock weather at different rates due to variations in their composition, structure, or exposure. This is a prominent feature in deserts due to:

* Extreme temperature swings: Rapid heating and cooling causes expansion and contraction, leading to stress and breakdown of rock.

* Limited moisture: While infrequent, intense rainstorms can rapidly erode exposed surfaces, leaving more resistant parts intact.

Let's look at the other options:

* Spheroidal weathering: This refers to the rounding of angular rocks, often due to chemical weathering processes. It can occur in deserts, but isn't the most characteristic type.

* Hydrolysis: This is a chemical weathering process involving the reaction of water with minerals, leading to their breakdown. While some hydrolysis can occur in deserts, it's less significant than other weathering processes.

* Sedimentation: This is the process of depositing sediments, typically through erosion and transport. It's not a type of weathering itself, but a result of weathering and other processes.

In summary: Differential weathering is the most prominent and characteristic type of weathering observed in desert environments.