LSAT Evaluate the Argument Questions Practice Questions with Answers

Critical reasoning skills are tested on the Law School Admission Test through various formats, but few are as strategically important as the LSAT Evaluate the Argument questions. These questions require you to identify the specific information that would be most helpful in determining the validity of a given conclusion. By focusing on the logical gap between a set of premises and the final claim, you can pinpoint exactly what data is missing to prove or disprove the author's point. This skill is a cornerstone of the LSAT Prep curriculum, as it mirrors the real-world legal task of assessing the strength of a case based on available evidence.

Concept Explanation

LSAT Evaluate the Argument questions are logical reasoning tasks that ask you to identify the question or piece of information whose answer would most effectively test the strength of the argument's conclusion. To succeed, you must first deconstruct the argument into its premises and conclusion, then look for the "missing link" or hidden assumption that the author relies upon. The correct answer choice will be a question that, depending on its answer, could either significantly strengthen or significantly weaken the argument. A common technique for verifying the correct choice is the "Variance Test": if providing two opposite answers to the question in the choice (e.g., "Yes" vs. "No") results in one answer supporting the conclusion and the other undermining it, you have found the correct response.

Solved Examples

1. Example 1: The Health Supplement Argument
   Argument: A new herbal supplement, Herb-X, was given to 100 participants who reported feeling more energetic. Therefore, Herb-X is effective at increasing energy levels.
   Solution:
   1. Identify the conclusion: Herb-X is effective at increasing energy.
   2. Identify the premise: 100 people took it and felt more energetic.
   3. Find the gap: We don't know if these people would have felt energetic anyway (placebo effect or external factors).
   4. Evaluate: The question "Did a control group not taking Herb-X also report increased energy?" is the best evaluation. If yes, the argument is weak; if no, it is stronger.
2. Example 2: The Corporate Revenue Argument
   Argument: TechCorp’s revenue increased by 20% this year. Since the only major change was the hiring of a new CEO, the new CEO is responsible for the growth.
   Solution:
   1. Identify the conclusion: The new CEO caused the 20% growth.
   2. Identify the premise: Revenue rose 20% and a new CEO was hired.
   3. Find the gap: The argument assumes no other factors (like industry-wide trends) caused the growth.
   4. Evaluate: The question "Did other companies in the same industry also experience a 20% revenue increase?" is crucial. If they did, the CEO's impact is questionable.
3. Example 3: The Rare Bird Argument
   Argument: Birdwatchers spotted a rare Blue Heron in the local marsh yesterday. Because this heron only migrates when temperatures drop below $10^{\circ} \text{C}$, the temperature must have been below $10^{\circ} \text{C}$ yesterday.
   Solution:
   1. Identify the conclusion: The temperature was below $10^{\circ} \text{C}$.
   2. Identify the premise: A Blue Heron was spotted; they migrate when it's below $10^{\circ} \text{C}$.
   3. Find the gap: The argument assumes the heron was migrating and not there for another reason (like being a local resident or lost).
   4. Evaluate: The question "Was the spotted heron a member of a local year-round population?" helps. If yes, the temperature claim is unsupported.

Practice Questions

1. A local bookstore saw a 50% increase in sales of mystery novels after moving them to the front of the store. The manager concludes that the new location is the sole reason for the sales spike. Which of the following would be most important to know to evaluate the manager's conclusion?

2. Recent data shows that students who use a specific digital AI Lecture Notes Enhancer score 15% higher on exams than those who take traditional notes. Educators argue that the tool directly improves cognitive retention. Which of the following questions is most relevant to evaluating this argument?

3. A city council proposes increasing the number of streetlights to reduce nighttime crime. They point to a nearby city where crime dropped after new lights were installed. To evaluate this proposal, it would be most useful to determine:

4. An environmentalist claims that a new factory is polluting the river because the fish population has declined by 30% since the factory opened. Which of the following would be most helpful in evaluating the environmentalist's claim?

5. A study found that people who drink four cups of coffee a day have a lower risk of heart disease. The researchers conclude that coffee contains compounds that protect the heart. To evaluate this, one should ask:

6. The government of Country X claims that its new tax policy has reduced unemployment, citing a 2% drop in the unemployment rate since the policy was enacted. Which of the following is most important to know to evaluate this claim?

7. A software company claims their new encryption method is unbreakable because no hackers have breached it in the three months since its release. To evaluate this claim, it would be most useful to know:

8. A nutritionist argues that a high-protein diet is better for weight loss because a group on that diet lost more weight than a group on a high-carb diet. Which of the following questions would best evaluate this argument?

Answers & Explanations

1. Answer: Did the bookstore run a major promotion on mystery novels during the same period?
   Explanation: If there was a promotion, the sales spike might be due to price rather than location. If there was no promotion, the location argument is much stronger.
2. Answer: Were the students who used the AI tool already higher-achieving students before using it?
   Explanation: This addresses potential selection bias. If high-achievers chose the tool, the tool itself might not be the cause of the higher scores.
3. Answer: Did the nearby city also increase police patrols at the same time the lights were installed?
   Explanation: This identifies a confounding variable. If patrols increased, the lights might not be the reason crime dropped.
4. Answer: Has there been a similar decline in fish populations in nearby rivers without factories?
   Explanation: This helps determine if the decline is a regional trend (like a drought) rather than a factory-specific issue.
5. Answer: Do the coffee drinkers also engage in more physical exercise than non-coffee drinkers?
   Explanation: This tests for a correlation vs. causation error. Exercise could be the real protective factor.
6. Answer: Did the total number of people in the labor force change significantly during that period?
   Explanation: If many people stopped looking for work, they are no longer counted as "unemployed," which would lower the rate without the policy actually creating jobs.
7. Answer: How many sophisticated hacking attempts were actually made against the software during those three months?
   Explanation: If no one tried to break it, the fact that it wasn't broken doesn't prove it is "unbreakable."
8. Answer: Were the total caloric intakes of the two groups approximately equal?
   Explanation: If the protein group ate fewer calories overall, the weight loss might be due to a caloric deficit rather than the macronutrient ratio.

Frequently Asked Questions

What is the difference between "Strengthen" and "Evaluate" questions?

Strengthen questions ask for information that makes the conclusion more likely to be true, whereas Evaluate questions ask for a question whose answer could either strengthen or weaken the argument. Essentially, an Evaluate answer choice is a "Strengthen/Weaken" hybrid.

How does the Variance Test work?

To use the Variance Test, you take an answer choice and provide two extreme, opposite responses to it. If one response makes the argument much stronger and the other makes it much weaker, that choice is the correct evaluation of the argument.

Are Evaluate the Argument questions common on the LSAT?

While they are less frequent than Flaw or Support questions, they appear regularly in the Logical Reasoning sections. Mastering them is essential for reaching the higher score brackets where every point counts.

Can an Evaluate question have a "Yes/No" answer?

Yes, many Evaluate the Argument questions are phrased as "Whether..." or "Is..." questions where a "Yes" answer might support the conclusion and a "No" answer might undermine it, or vice versa.

Should I look for the flaw first?

Yes, because Evaluate questions are often based on a logical flaw or a missing assumption. Identifying why the argument isn't currently airtight will lead you directly to the information needed to evaluate it properly.

What if two answers seem relevant?

Apply the Variance Test to both; the correct answer will have a much more significant impact on the conclusion's validity. One might be slightly interesting, but the other will be logically decisive.