Dr. Ima Quack's statement is an example of a scare tactic .
A scare tactic is a persuasive strategy that uses fear to influence people's thoughts or actions. In this context, Dr. Quack claims that most Americans suffer from nutritional deficiencies and are at risk of developing cancer unless they take her megavitamin formula. This statement instills fear by suggesting dire health consequences while promoting her product as the only solution.
Scare tactics can often be misleading, as they may not be based on scientific evidence or might exaggerate potential outcomes to manipulate an audience. It's important to critically evaluate such statements and seek reliable scientific data before making health-related decisions.