Which term describes a situation that lacks clarity?

The term that describes a situation lacking clarity is "ambiguous." When something is ambiguous, it means that it can be understood in more than one way or that it is uncertain and not clearly defined. This quality can lead to confusion, as the information at hand doesn't provide a straightforward interpretation or meaning. In contrast, "explicit" refers to something that is clearly and plainly expressed, thereby providing no ambiguity. "Lucid" also signifies clarity and understanding, often used to describe thoughts or expressions that are clear and easy to understand. "Ostensible" means something that appears to be one way on the surface but may not reflect the underlying reality, which does not accurately convey a lack of clarity in a situation. Therefore, "ambiguous" is the most fitting term when referring to unclear situations.