8. CAROLINE WOZNIACKI
Wozniacki's grunt is more of a quiet "unf." That is, until a challenger rises to the occasion. While playing Victoria Azarenka, Wozniacki met her eccentric grunts with her own quiet response, until Azarenka let out a painful yet attention-grabbing scream. Not to be outdone, Wozniacki then met Azarenka's yell with her a scene-stealing and hearing-aid-busting banshee impression.