What does undue influence require beyond mere susceptibility?

Undue influence in the context of wills and trusts focuses on the manipulation or coercion of a testator by another party, which results in the testator's decisions about their estate that may not reflect their true intentions. To establish undue influence, it is essential to demonstrate not only that the testator was susceptible to influence (due to factors like age, mental capacity, or emotional dependence) but also that the influencer's actions led to a disproportionate benefit for themselves.

Option C accurately highlights this aspect by specifying the need for evidence that the influencer received a benefit that was not justifiable in relation to the circumstances or the testator’s intentions. This element emphasizes the exploitative nature of undue influence, showing that the influencer took advantage of their position to secure a gain that they might not have received otherwise.

In contrast, the other options do not effectively capture the essence of what is required to prove undue influence. Legal representation during will drafting, documentation of the testator's mental state, and a formal will execution ceremony may all be relevant in different contexts, but they do not specifically address the critical component of demonstrating that the influencer received an unfair or disproportionate advantage as a result of their influence over the testator.