Final answer:
Testimonial is the advertising technique that shows a celebrity endorsing a product.
Step-by-step explanation:
The correct answer is
testimonial. Testimonial is an advertising technique that involves a celebrity endorsing a product. This technique is used to create a positive association between the product and the celebrity's image or reputation. An example would be a famous athlete promoting a sports drink, emphasizing that it is the key to their success and performance.
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