What is the purpose of the IComparable interface in C#?

The IComparable interface in C# serves as a contract that dictates how two objects should be compared for sorting or ordering purposes. By implementing this interface, a class can provide its own comparison logic via the CompareTo method, which compares the current instance with another object of the same type. This functionality is crucial for sorting collections of objects, as it allows data structures like arrays or lists to order their elements based on customized criteria defined by the programmer.

In essence, when a class implements IComparable, it enables instances of that class to be sorted in a predictable manner, which is foundational in many programming scenarios, such as displaying lists of items, implementing search functionality, or simply organizing data. This interface is a cornerstone of the sorting mechanism in .NET, making it indispensable for any developer working with collections of custom objects.

The other choices relate to concepts that are not applicable to the primary purpose of the IComparable interface.