Which of the following is an effective way to establish credibility as a speaker?

Establishing credibility as a speaker largely hinges on how knowledgeable and trustworthy the audience perceives you to be. Presenting well-researched information is a vital component of this credibility. When you provide data, statistics, and facts that are thoroughly vetted and sourced, it demonstrates your preparation and expertise on the topic. This not only bolsters your authority but also instills confidence in your audience regarding the accuracy of the material you are discussing.

While other options like wearing professional attire or speaking clearly can also contribute to a speaker's professionalism and effectiveness, they do not serve the same foundational role in establishing credibility as the depth and quality of your knowledge. Humor, while it can engage the audience, does not necessarily enhance your perceived expertise or reliability on the subject matter, which makes well-researched information the more impactful choice for establishing credibility.