Final answer:
The terms 'Z: zombie' and 'D: do not disturb' are best described as process states in the context of an operating system.
Step-by-step explanation:
The terms Z: zombie and D: do not disturb are related to process states in computing. In the context of an operating system, a zombie process is a process that has completed its execution but still has an entry in the process table. This state occurs when the process has been terminated, but its parent process has not yet called wait(), which is necessary to read the child's exit status and to remove the entry from the process table. Alternatively, 'Do Not Disturb' could be related to settings in software applications that, when enacted, suppresses notifications to avoid interruptions. However, as per the context provided, these terms are best described as process states.