Which influence tactic of social proof is not used by the following social shopping tools?

Name: Which influence tactic of social proof is not used by the following social shopping tools?
Brand: Quizplus
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Question

Quizplus · Accepted Answer

D)Social media marketers who want to win customers find it helpful to understand what we know more generally about the psychology of influence the factors that make it more or less likely that people will change their attitudes or behavior based on a persuasive message.

Which Influence Tactic of Social Proof Is Not Used by the Following