Formal.
As far as I know, there is no such thing as either standard or practiced diction. Informal is the way you communicate with your friends, for instance, which is not how you would write a thesis paper, legal document, etc.
Advertising can both help us and harm us. One way advertising could harm us is by saying that a product could work and not state the dangers of the product. For example with the iPhone 12s they’re causing death to certain people with medical issues. One way advertising can help us by helping us find things that we could need in our everyday lives. For example having an plumbing issue and you see an advertisement for an plumbing company would you most likely try to get help from them.
Disguise would the answer for your question