Studies of Vocal Variety Showed All of the Following EXCEPT

Studies of vocal variety showed all of the following EXCEPT that

A) when read to out loud, audiences exposed to speakers who used large variations in rate, force, pitch, and voice quality retained more information.
B) audience comprehension of prose and poetry fell 10% when the author spoke in a monotone voice.
C) skilled speakers are more effective than unskilled ones whether the material is organized or disorganized, easy or difficult.
D) neither understanding nor recall improved when the message was delivered by a skilled speaker.