which choice is the most effective way to involve members of an audience?
a.
direct questions to the audience to encourage participation.
b.
state your opinion often to prove your knowledge of the topic.
c.
smile and use a soothing voice as you present.
d.
cut out parts of the speech to make it shorter.

The answer is A: direct questions to the audience to encourage participation.

 There are many ways that the speaker uses to demonstrate his or her interest and interation with the audience such as eye-contact, tone of voice etc. However, directing questions is the most effective way to involve the audience which helps them feel more than mere spectators, specially if is allowed time for them to answer followed by some recognition for their contribution.

A.  Direct questions to the audience to encourage participation.

When trying to engage an audience, the best thing to do is encourage participation.  This can be done by asking them direct questions.  This can also be done by asking them rhetorical questions in order to get the audience to directly engage mentally with an idea presented.  Additionally, there can also be instances where the audience interacts with each other as this way each audience member becomes engaged.  However, for the sake of time and direct speaker/audience member interaction, the best way to do this by asking direct questions.