Which of the following may negatively affect the delivery of a speech?

The correct answer relates to the impact that certain delivery techniques can have on audience engagement and perception. While varying voice and bodily action are typically positive elements that enhance a speech, if these elements are executed poorly or too excessively, they can become distracting. Overly dramatic voice changes or erratic movements may divert the audience’s attention away from the message being conveyed, leading to confusion or disengagement.

In contrast, citing sources of information serves to enhance credibility and supports the speaker's arguments, thereby positively affecting delivery. Pausing at transitional points can actually provide clarity and allow the audience to digest information, promoting better understanding. Making gestures below the waist may not necessarily enhance a speech’s effectiveness, but it tends to be less noticeable than gestures made above the waist; thus, it's not as impactful negatively on delivery as improperly varying voice and bodily action may be.