It really isn't bandwagon because only one person is featured with this product. Check this site to find a technique that better describes this ad.
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Supermodel Tyra Banks uses Smooth & Soft bath gel; you should, too! Is this bandwagon? I think so.
3 answers
Propaganda is what I originally thought, but my only choices are, faulty cause and effect, red herring, bandwagon, either/or thinking, testimonial, or stereotype. I know that it's not stereotype.
It looks like a testimonial, with the supermodel praising it.