Final answer:
Making a bandwagon appeal in a persuasive speech is an example of using an unsubstantiated opinion.
Step-by-step explanation:
In a persuasive speech, making a bandwagon appeal is an example of using an unsubstantiated opinion. This appeal technique involves persuading the audience to agree with a certain viewpoint or take a specific action by suggesting that everyone else is doing it. However, it does not provide any real evidence or facts to support the opinion being presented.
Learn more about bandwagon appeal