An LSAT Logical Reasoning question type that asks which new piece of information, if true, would most seriously undermine the argument's support for its conclusion. Recognition: "Which, if true, most seriously weakens the argument?" The task is to widen the gap between premises and conclusion — typically by introducing an alternative explanation, identifying an overlooked difference, or attacking the argument's central assumption. Weaken answers do not have to disprove the conclusion; they only need to reduce the likelihood that the premises support it.