LSAT Logical Reasoning: Strengthen and Support Questions

Question 1

A scientist argues that a newly discovered bacterium causes a specific skin disease because patients with the disease all test positive for the bacterium.
Which of the following, if true, most strengthens this argument?

Accepted Answer

Healthy individuals without the skin disease consistently test negative for the bacterium.

Answer

The bacterium was discovered in a research laboratory.

Answer

The skin disease affects approximately 2% of the population.

Answer

The bacterium is similar in structure to other known pathogens.

Answer

The disease has been observed in multiple countries.

Question 2

A city argues that its new after-school tutoring program increased graduation rates, pointing to a rise from 78% to 85% graduation rate after implementation. Which of the following most strengthens this argument?

Accepted Answer

Neighboring cities without similar programs showed no comparable improvement in graduation rates during the same period.

Answer

The tutoring program employed certified teachers.

Answer

The program served 300 students in its first year.

Answer

Tutoring has been shown to improve academic confidence.

Answer

The program was funded by a federal education grant.

Question 3

A nutritionist argues that a specific probiotic supplement improves digestive health in adults with irritable bowel syndrome (IBS). Which of the following most strengthens this argument?

Accepted Answer

In a randomized controlled trial, IBS patients taking the probiotic reported significantly fewer symptoms than those receiving a placebo.

Answer

The probiotic was developed by a team of gastroenterologists.

Answer

Probiotics are generally recognized as safe by regulatory agencies.

Answer

The supplement contains five distinct bacterial strains.

Answer

IBS affects millions of people worldwide.

Question 4

An archaeologist argues that a coastal settlement was abandoned due to rising sea levels, rather than warfare or disease. Which of the following most strengthens this argument?

Accepted Answer

Sediment core samples from the region show evidence of rapid sea-level rise occurring precisely at the time of the abandonment, with no evidence of mass casualties or violent destruction.

Answer

The settlement shows signs of rapid abandonment rather than gradual decline.

Answer

Similar settlements in the same era were also abandoned.

Answer

The inhabitants of the settlement were skilled fishermen.

Answer

Historical records from the period are incomplete.

Question 5

A health researcher argues that moderate coffee consumption (2-3 cups daily) reduces the risk of type 2 diabetes. Which of the following most strengthens this argument?

Accepted Answer

A mechanism has been identified: compounds in coffee improve insulin sensitivity by activating specific cellular receptors.

Answer

Coffee is one of the most widely consumed beverages globally.

Answer

Type 2 diabetes rates have been rising globally.

Answer

The research was funded by an independent health foundation.

Answer

People who drink coffee tend to be more socially active.

Question 6

A geologist argues that a particular rock formation was created by a massive ancient volcanic eruption rather than gradual sedimentary processes. Which of the following most strengthens this argument?

Accepted Answer

The rock formation contains minerals that can only form under the extreme heat and pressure conditions produced by volcanic eruptions, not sedimentary processes.

Answer

Volcanic rock formations can be visually similar to sedimentary formations.

Answer

The formation is located near a known ancient volcanic region.

Answer

Geologists have studied similar formations for decades.

Answer

Rock dating methods have become increasingly precise.

Question 7

A social scientist argues that income inequality causes social unrest, citing a correlation between higher inequality (measured by Gini coefficient) and greater political instability across countries. Which of the following most strengthens this argument?

Accepted Answer

Historical analysis shows that periods of increasing inequality in stable societies are reliably followed by increases in social unrest, before external factors changed.

Answer

The Gini coefficient is a commonly used measure of income distribution.

Answer

Some highly unequal countries have remained politically stable for decades.

Answer

Political scientists disagree about the causes of social unrest.

Answer

International organizations track income inequality data annually.

Question 8

A pharmaceutical researcher argues that a new antibiotic is effective against a drug-resistant bacterial strain. Which of the following most strengthens this argument?

Accepted Answer

Laboratory tests show the antibiotic kills the resistant strain at low concentrations, and animal trials show complete infection clearance with no evidence of new resistance developing.

Answer

The antibiotic was developed using a novel molecular targeting approach.

Answer

Drug-resistant bacteria pose a major threat to public health.

Answer

The research team has published studies on antibiotic resistance.

Answer

Previous antibiotics have failed against this bacterial strain.

Question 9

An economist argues that trade liberalization increases economic growth in developing countries. Which of the following most strengthens this argument?

Accepted Answer

Countries that liberalized trade showed accelerated GDP growth in the years following liberalization, while those that did not liberalize showed no comparable growth acceleration despite similar starting conditions.

Answer

Trade liberalization involves reducing tariffs and import quotas.

Answer

Some economists oppose free trade agreements.

Answer

Developing countries face many economic challenges beyond trade policy.

Answer

International trade volumes have increased substantially over the past 50 years.

Question 10

A psychologist argues that cognitive behavioral therapy (CBT) is more effective than medication alone for treating panic disorder. Which of the following most strengthens this argument?

Accepted Answer

In a study where panic disorder patients were randomly assigned to CBT, medication, or combined treatment, CBT patients showed lower relapse rates at 12-month follow-up than medication-only patients.

Answer

CBT helps patients identify and challenge irrational thought patterns.

Answer

Panic disorder is characterized by recurring unexpected panic attacks.

Answer

CBT requires more sessions than medication management.

Answer

Many therapists are trained in CBT techniques.