Which word signifies something that is impossible to validate?

The word "void" is significant in this context because it conveys the idea of emptiness or lack of substance, which aligns with the concept of something that cannot be validated. When something is described as void, it suggests that there is no tangible evidence or basis to support its existence or claim, making it impossible to prove or validate.

In contrast, the other options do not fit this meaning. For instance, "witty" refers to a person’s ability to use words in a clever and humorous way, which has no relation to validation. Similarly, "yearning" describes a deep longing or desire, not the inability to validate something. Meanwhile, "verifiable" pertains explicitly to something that can be confirmed or validated, which is the opposite of what the question is asking for. Therefore, "void" accurately captures the essence of something that lacks confirmation or validation.