Final answer:
The statement that advertising effectiveness is based solely on persuading audiences is most undermined by the strategy of designing controversial ad campaigns to gain free media coverage, as this indicates other factors contribute to campaign effectiveness.
Step-by-step explanation:
The provided statements, if true, most seriously undermine assertion (A): The usefulness of an advertising campaign is based solely on the degree to which the campaigns advertisements persuade their audiences. This is because the strategy discussed involves generating free publicity and air time by creating controversial ad campaigns that draw media attention and evoke public comment, rather than simply persuading audiences through the content of the advertisements themselves. Therefore, this strategy suggests that there are factors other than direct persuasion that can contribute to the effectiveness of an advertising campaign.
Additionally, the information suggests that advertising techniques and the media landscape have evolved over time. Corporate advertising has shifted to strategies that ensure brand recognition and visibility across multiple platforms. Similarly, political campaign strategies now include a variety of media, including Internet and social media, to target different demographic groups.