What does a 'kill signal' do to a process?

A 'kill signal' is primarily used to terminate a process in a Unix-like operating system. When a kill signal is sent to a process, it instructs the operating system to stop the process execution. The most common kill signal is SIGTERM, which requests the process to terminate gracefully, allowing it to clean up resources and save its state if necessary. However, if the process does not terminate in response to this signal, a more forceful signal such as SIGKILL can be used, which immediately terminates the process without allowing for cleanup. Therefore, the function of a kill signal is to halt a process, which is why this answer is the correct choice.

Other options incorrectly describe the functionalities associated with process management in a Unix/Linux environment. For instance, pausing a process is handled by sending a SIGSTOP signal instead, while restarting a process requires a different mechanism, such as executing the process anew. Changing a process's priority involves using the nice or renice commands, not a kill signal. Hence, only the description of stopping a process aligns with the behavior of a kill signal.