Which Statement Best Describes the Use of Testimonials as Part

Which statement best describes the use of testimonials as part of one's advertising campaign?

A) Such ads are strictly prohibited.
B) Tests are only required if the ad claims the product will provide a savings to consumers.
C) Such ads are regarded as "puffery" and do not attract scrutiny of regulatory authorities.
D) Using a well known personality will attract close scrutiny by regulatory authorities.