Answer:
gain audience attention and interest.
enhance the presenter’s credibility.
Explanation:
When you are going to introduce the presenter to a lecture, it is important that you gain public attention and interest in the subjects that will be addressed by the presenter. In this case, you can present who the presenter is and what he is going to talk about, emphasizing the relevance of this subject and the presentation as a whole. In addition, it is important to emphasize why this presenter should be heard, presenting the reasons that make him a qualified person to present the given subject, which allows the presenter's credibility to be improved.
I think the answer is a) dislocation. That is just a guess so I might not be right.
The answer is A because the rest would incomplete sentences
