In the context of delivering a presentation, which of the following is true of vocal qualities?

A) Verbal fillers better the style of a speech.
B) Pleasant voices have high pitch.
C) A varied pitch pattern is desirable during presentations.
D) A fast rate of speech is required when presenting a complex concept.

A varied pitch pattern, including changes in tone, volume, and pace, keeps the audience engaged and helps convey important points. Verbal fillers should be avoided to prevent distracting the audience. Pleasant voices can have a range of pitches, depending on the speaker's natural tone and the audience's preferences. The rate of speech should be appropriate for the audience's comprehension level and the complexity of the topic being discussed; there is no universal requirement for a fast or slow pace.