Microsoft Certified Solutions Developer (MCSD) Certification Practice Test

The appropriate method to signal that a thread's work is completed when using an `EventWaitHandle` is the `Set` method. The `Set` method is used to change the state of the `EventWaitHandle` to signaled, which allows any waiting threads to proceed.

In the context of multithreading, when a thread has finished its work, it can call `Set` to notify other threads that they can continue their execution. This mechanism is crucial for coordinating thread execution and resource access in a concurrent environment, ensuring that threads can efficiently wait for certain conditions to be met before proceeding.

Other methods or terms suggested, such as "Signal," "Complete," and "Finish," do not correspond to a predefined method for `EventWaitHandle` in the .NET framework. The terminology can cause confusion, as it's common to discuss signaling in the context of multithreading, but the specific method to use for changing the state of an `EventWaitHandle` is `Set`. This choice reinforces best practices in using synchronization primitives in .NET applications.