LSAT® Exam Prep 2026 Updated Practice Questions,
Comprehensive Law School Admission Test Review
Logical Reasoning Strategies, Verified Answers,
Success Workbook
1. All mammals are warm-blooded. Some warm-blooded animals are
nocturnal. Nocturnal animals have excellent night vision. Which one of the
following must be true?
A) All mammals are nocturnal.
B) Some mammals have excellent night vision.
C) Some warm-blooded animals have excellent night vision.
D) All nocturnal animals are mammals.
Rationale:
• A is incorrect: The stimulus only states that some warm-blooded animals
are nocturnal, not all. Mammals are a subset of warm-blooded animals, so
we cannot conclude all mammals are nocturnal.
• B is incorrect: We know some warm-blooded animals are nocturnal, and all
nocturnal animals have excellent night vision. However, we do not know
whether any of those nocturnal warm-blooded animals are mammals.
Mammals are warm-blooded, but the nocturnal warm-blooded
animals could be non-mammals.
• C is correct: Since some warm-blooded animals are nocturnal, and all
nocturnal animals have excellent night vision, it necessarily follows that at
least some warm-blooded animals (specifically, the nocturnal ones) have
excellent night vision.
• D is incorrect: The relationship is reversed. The stimulus states that some
warm-blooded animals are nocturnal — it does not state that all nocturnal
animals are warm-blooded or mammals.
2. Economist: A country's economic growth is determined primarily by its
level of investment in education and infrastructure. However, increased
,investment in education does not always lead to economic growth unless
accompanied by political stability. Political stability alone, without education
investment, also does not guarantee growth. Which one of the following is
most strongly supported by the economist's statements?
A) Political stability is more important than education investment for economic
growth.
B) Economic growth requires both education investment and political
stability.
C) Countries with political stability always experience economic growth.
D) Education investment is the only factor that determines economic growth.
Rationale:
• A is incorrect: The economist does not compare the relative importance of
the two factors; both are presented as necessary conditions for growth.
• B is correct: The economist states that education investment alone is
insufficient without political stability, and political stability alone is
insufficient without education investment. This supports the conclusion
that both are required for economic growth.
• C is incorrect: Political stability alone is stated as insufficient for growth.
• D is incorrect: The economist explicitly states that both education and
political stability matter.
3. The mayor claims that the new public transportation system has reduced
traffic congestion by 20%. However, during the same period, the city
implemented a congestion pricing program and expanded remote work
options. Which one of the following, if true, most weakens the mayor's claim?
A) The congestion pricing program was unpopular with commuters.
B) Traffic congestion decreased in neighboring cities that did not implement any of
these measures.
C) Remote work options expanded significantly during the same period and
are known to reduce traffic.
D) The new transportation system was completed on time and within budget.
Rationale:
, • A is incorrect: Unpopularity does not weaken the claim about the
transportation system's effectiveness.
• B is incorrect: This actually strengthens the mayor's claim by showing
broader regional trends.
• C is correct: If remote work expansion is a known cause of traffic
reduction, then the reduction cannot be attributed solely to the new
transportation system. This provides an alternative explanation for the
observed decrease.
• D is incorrect: Being on time and within budget is irrelevant to whether the
system caused the traffic reduction.
4. All successful entrepreneurs are risk-takers. Some risk-takers are not
successful. No risk-taker is risk-averse. Which one of the following must be
true?
A) Some successful entrepreneurs are risk-averse.
B) No successful entrepreneur is risk-averse.
C) All risk-takers are successful.
D) Some risk-averse people are successful entrepreneurs.
Rationale:
• A is incorrect: If all successful entrepreneurs are risk-takers, and no risk-
taker is risk-averse, then no successful entrepreneur can be risk-averse.
• B is correct: Since all successful entrepreneurs are risk-takers, and no risk-
taker is risk-averse, it necessarily follows that no successful entrepreneur
is risk-averse.
• C is incorrect: The stimulus explicitly states that some risk-takers are not
successful.
• D is incorrect: This contradicts the conclusion that no successful
entrepreneur is risk-averse.
5. A study found that people who drink at least two cups of coffee per day
have a lower risk of developing Type 2 diabetes than those who drink no
, coffee. The study's authors concluded that coffee consumption reduces the
risk of diabetes. Which one of the following, if true, most weakens the
conclusion?
A) Coffee drinkers tend to exercise more regularly than non-coffee drinkers.
B) Coffee drinkers tend to exercise more regularly than non-coffee drinkers.
C) The study was funded by a major coffee company.
D) The study followed participants for 10 years.
Rationale:
• A is correct: If coffee drinkers exercise more regularly, then the reduced
diabetes risk may be due to exercise rather than coffee consumption. This
provides an alternative explanation for the observed correlation.
• B is incorrect: This is the same as A.
• C is incorrect: While funding source can raise concerns, it does not by itself
weaken the scientific conclusion.
• D is incorrect: A 10-year follow-up is a methodological strength, not a
weakness.
6. Politician: Our country must either increase taxes or cut spending to reduce
the deficit. Since raising taxes would harm economic growth, we must cut
spending. Which one of the following is an assumption required by the
politician's argument?
A) Cutting spending would not harm economic growth.
B) There are no other options for reducing the deficit.
C) The public would support cutting spending.
D) Economic growth is more important than deficit reduction.
Rationale:
• A is incorrect: The politician does not claim cutting spending
would not harm growth; they only claim raising taxes would harm growth.
The argument could still work even if spending cuts also harmed growth.
• B is correct: The politician presents a false dichotomy: either increase taxes
or cut spending. The argument assumes there are no other viable
Comprehensive Law School Admission Test Review
Logical Reasoning Strategies, Verified Answers,
Success Workbook
1. All mammals are warm-blooded. Some warm-blooded animals are
nocturnal. Nocturnal animals have excellent night vision. Which one of the
following must be true?
A) All mammals are nocturnal.
B) Some mammals have excellent night vision.
C) Some warm-blooded animals have excellent night vision.
D) All nocturnal animals are mammals.
Rationale:
• A is incorrect: The stimulus only states that some warm-blooded animals
are nocturnal, not all. Mammals are a subset of warm-blooded animals, so
we cannot conclude all mammals are nocturnal.
• B is incorrect: We know some warm-blooded animals are nocturnal, and all
nocturnal animals have excellent night vision. However, we do not know
whether any of those nocturnal warm-blooded animals are mammals.
Mammals are warm-blooded, but the nocturnal warm-blooded
animals could be non-mammals.
• C is correct: Since some warm-blooded animals are nocturnal, and all
nocturnal animals have excellent night vision, it necessarily follows that at
least some warm-blooded animals (specifically, the nocturnal ones) have
excellent night vision.
• D is incorrect: The relationship is reversed. The stimulus states that some
warm-blooded animals are nocturnal — it does not state that all nocturnal
animals are warm-blooded or mammals.
2. Economist: A country's economic growth is determined primarily by its
level of investment in education and infrastructure. However, increased
,investment in education does not always lead to economic growth unless
accompanied by political stability. Political stability alone, without education
investment, also does not guarantee growth. Which one of the following is
most strongly supported by the economist's statements?
A) Political stability is more important than education investment for economic
growth.
B) Economic growth requires both education investment and political
stability.
C) Countries with political stability always experience economic growth.
D) Education investment is the only factor that determines economic growth.
Rationale:
• A is incorrect: The economist does not compare the relative importance of
the two factors; both are presented as necessary conditions for growth.
• B is correct: The economist states that education investment alone is
insufficient without political stability, and political stability alone is
insufficient without education investment. This supports the conclusion
that both are required for economic growth.
• C is incorrect: Political stability alone is stated as insufficient for growth.
• D is incorrect: The economist explicitly states that both education and
political stability matter.
3. The mayor claims that the new public transportation system has reduced
traffic congestion by 20%. However, during the same period, the city
implemented a congestion pricing program and expanded remote work
options. Which one of the following, if true, most weakens the mayor's claim?
A) The congestion pricing program was unpopular with commuters.
B) Traffic congestion decreased in neighboring cities that did not implement any of
these measures.
C) Remote work options expanded significantly during the same period and
are known to reduce traffic.
D) The new transportation system was completed on time and within budget.
Rationale:
, • A is incorrect: Unpopularity does not weaken the claim about the
transportation system's effectiveness.
• B is incorrect: This actually strengthens the mayor's claim by showing
broader regional trends.
• C is correct: If remote work expansion is a known cause of traffic
reduction, then the reduction cannot be attributed solely to the new
transportation system. This provides an alternative explanation for the
observed decrease.
• D is incorrect: Being on time and within budget is irrelevant to whether the
system caused the traffic reduction.
4. All successful entrepreneurs are risk-takers. Some risk-takers are not
successful. No risk-taker is risk-averse. Which one of the following must be
true?
A) Some successful entrepreneurs are risk-averse.
B) No successful entrepreneur is risk-averse.
C) All risk-takers are successful.
D) Some risk-averse people are successful entrepreneurs.
Rationale:
• A is incorrect: If all successful entrepreneurs are risk-takers, and no risk-
taker is risk-averse, then no successful entrepreneur can be risk-averse.
• B is correct: Since all successful entrepreneurs are risk-takers, and no risk-
taker is risk-averse, it necessarily follows that no successful entrepreneur
is risk-averse.
• C is incorrect: The stimulus explicitly states that some risk-takers are not
successful.
• D is incorrect: This contradicts the conclusion that no successful
entrepreneur is risk-averse.
5. A study found that people who drink at least two cups of coffee per day
have a lower risk of developing Type 2 diabetes than those who drink no
, coffee. The study's authors concluded that coffee consumption reduces the
risk of diabetes. Which one of the following, if true, most weakens the
conclusion?
A) Coffee drinkers tend to exercise more regularly than non-coffee drinkers.
B) Coffee drinkers tend to exercise more regularly than non-coffee drinkers.
C) The study was funded by a major coffee company.
D) The study followed participants for 10 years.
Rationale:
• A is correct: If coffee drinkers exercise more regularly, then the reduced
diabetes risk may be due to exercise rather than coffee consumption. This
provides an alternative explanation for the observed correlation.
• B is incorrect: This is the same as A.
• C is incorrect: While funding source can raise concerns, it does not by itself
weaken the scientific conclusion.
• D is incorrect: A 10-year follow-up is a methodological strength, not a
weakness.
6. Politician: Our country must either increase taxes or cut spending to reduce
the deficit. Since raising taxes would harm economic growth, we must cut
spending. Which one of the following is an assumption required by the
politician's argument?
A) Cutting spending would not harm economic growth.
B) There are no other options for reducing the deficit.
C) The public would support cutting spending.
D) Economic growth is more important than deficit reduction.
Rationale:
• A is incorrect: The politician does not claim cutting spending
would not harm growth; they only claim raising taxes would harm growth.
The argument could still work even if spending cuts also harmed growth.
• B is correct: The politician presents a false dichotomy: either increase taxes
or cut spending. The argument assumes there are no other viable
