During a speech, the audience has doubts about whether this speaker is a reliable source of information about the topic. The speaker probably should have devoted more attention to during the speech.

establishing credibility.

Explanation:

Credibility refers to the foundation of being trusted by the audience. Credibility is attributable to the public's perception of the integrity and reputation of the speaker. Credibility depends on various factors such as self-presentation and expertise of the speaker. However, it should be noted that stressing too much on one's achievement loses the interest of audiences as they may start doubting the speaker.

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