Final answer:
Lady Gaga could potentially sue a clothing company using her style sense for their "Going Gaga" collection on the basis of unfair competition or trademark infringement, as her name and persona likely function as a trademark.
Step-by-step explanation:
A clothing company utilizing the style sense of singer Lady Gaga for a new clothing line without her permission could potentially face a lawsuit on the grounds of unfair competition or trademark infringement. Since Lady Gaga is a well-known figure, her name and associated personas are likely protected as a personal brand. If the use of her name or style in the "Going Gaga" collection suggests an endorsement or association that does not exist, Gaga's legal team might argue that the company is misappropriating her trademark. In certain cases, her unique style could be recognized as her trademark, particularly if used to signify her endorsement. Generally, copyright violation does not apply in this context since it protects original works of authorship, while defamation is about false statements that harm someone's reputation, neither of which directly relate to the described scenario.