Which strategy would likely be least effective in securing deep processing from a consumer?

Using a likable celebrity endorsing the product is least effective in securing deep processing from a consumer because it relies primarily on the peripheral route of persuasion rather than the central route. Deep processing occurs when individuals engage with the material in a meaningful way, analyzing, and reflecting on the information presented, which leads to better retention and attitude change.

While celebrity endorsements can attract attention and create a positive association with a product, they do not necessarily encourage consumers to evaluate the arguments or benefits of the product itself. Instead, consumers may focus more on the appeal of the celebrity and their likability, rather than the substantive qualities of the product. In contrast, strategies that provide statistical support for claims, engage with thought-provoking questions, or offer detailed information about product benefits encourage consumers to think critically and deeply about the product, leading to more meaningful processing and understanding.