Final answer:
Articulation is pivotal in establishing a speaker's credibility since it affects clarity and helps the audience understand and connect with the message. Rate of speech also impacts effectiveness but is not as directly influential as articulation. Option c is the correct answer.
Step-by-step explanation:
When it comes to enhancing a speaker's credibility, various factors contribute to how the audience perceives them. A key element is articulation, as it ensures clarity in the speech, allowing listeners to easily comprehend the message.
Good articulation means that words are pronounced distinctly and intelligibly, which fosters better understanding and connection between the speaker and the audience.
Rate of speech, or how fast or slow the speaker talks, plays a significant role in communication effectiveness. A speaker must find a balance that allows the audience to follow along without feeling rushed or bored. Volume and pitch also affect credibility, but they do not have as direct an impact as articulation and rate on the speaker's ability to be understood and taken seriously.
Lastly, confidence and expertise on the subject matter strongly support a speaker's credibility. Briefly stating one's credentials and experience showcases authority on the topic, thereby boosting the speaker's credibility. Therefore, while options such as volume and rate are important, it is articulation that directly influences the clarity of the speech and is pivotal in establishing a speaker's credibility.