This persuasive technique is called appeal to authority.
Appeal to authority is a persuasive technique where the speaker relies on the credibility of another person or event to suport their own argument. It is often considered a fallacy because the speaker depends on the "authority"instead of presenting their own evidence.
Example:
"A commercial claims that 3 out of 4 dentists would choose this particular brand of toothpaste for their own families to use."
In this statement, the dentists are the authority the argument depends on.
