Final answer:
Enunciation refers to the clear and distinct articulation of sounds when speaking, which involves proper movement of the mouth and vocal structures. It is not to be confused with pitch, which is related to the frequency of sound, nor volume, which pertains to the loudness of the speech.
Step-by-step explanation:
The question asks what enunciation refers to. Enunciation is the act of pronouncing words clearly and distinctly. It is most associated with option C) Articulation of clear sounds.
Articulation involves producing sounds clearly with precise movements of the lips, tongue, teeth, and palate. Clear articulation during a presentation ensures the audience understands the speaker's message without confusion.
Importantly, while words like 'pitch' and 'volume' might be part of effective speech delivery, they do not define enunciation. Pitch is the highness or lowness of a sound, as determined by its frequency. Volume relates to the loudness or softness of a person's voice. While both are important aspects of vocal delivery, they are not the same as enunciation.