The hardest LSAT practice questions (original, with explanations)

This is selection bias, the subtlest causal flaw: the sickest patients cluster where the specialists are, so the death rate reflects the patients, not the doctors. The correlation is real but the arrow is confounded by who goes where. B is true but secondary; the argument's core error is ignoring the sorting of patients.

Eliminating tailpipe emissions only meets the target if the fleet's emissions were a big enough slice of it and the buses actually run. The argument quietly assumes both scale and execution. Negate B: buses arrive late, run half-empty, and the target is missed despite zero tailpipes.

Both affirm the consequent: All A are B, X is B, so X is A. Thanking a mentor is necessary for winners, not sufficient to make one. A is valid, D hedges with "may," and E is a valid contrapositive.

This is the confounded-observational-study killer: the coffee group was healthier in every measured way, and the analysis never controlled for it. The "protection" could be wealth and exercise wearing a coffee costume. D is a real flaw but a smaller one; B attacks the causal inference itself.

Take someone present who approved the budget. By the first claim, that person cannot be a manager. So at least one budget-approver is not a manager. B overreaches: managers may have approved it from afar.

Stable numbers alone could hide a decline that would have happened anyway. The neighboring region supplies the missing counterfactual: without the increase, employment fell. Holding steady against a falling baseline is evidence of no harm, maybe even help.

Yusuf concedes the commute point (A is agreed) and Xena never disputes the wetland damage (C is effectively agreed). Each weighs the tradeoff differently: Xena says worth it, Yusuf says not. The disagreement is the bottom-line cost-benefit verdict.

The argument is an induction dressed as a deduction: past pattern plus current match. For the conclusion to follow logically, the past-to-future bridge must be airtight, which is exactly what A supplies. Without A, the past pattern is merely suggestive. E is tempting but narrower; A is the load-bearing assumption.

The speaker never argues mergers are bad (D) or predicts this one's outcome (B). It grants the "survival" framing, then shows the company's own numbers contradict the premise that survival is at stake. The justification collapses against undisputed facts.

Eliminating one rival does not crown the remaining suspect. The argument sets up a false exhaustive pair: curriculum or teachers. Easier exams, better-prepared students, or changed demographics could all explain the rise. Ruling out one alternative is not ruling out all of them.