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SAT Supporting & Undermining: Lesson, Practice Problems & Video Explanations

By Glyn Caddell, BSME · Author of Digital SAT Math Secrets · Tutoring since 2008 — Updated August 18, 2026

Digital SAT Supporting & Undermining Questions

Supporting & undermining questions ask students to choose the answer that would best strengthen or weaken a claim made in the text. Students need to understand the claim, the evidence already provided, and how new information would affect the argument. Supporting & undermining questions appear on approximately 7.3% of the Digital SAT Reading & Writing section. These questions fall under Information and Ideas according to the College Board categories.

Table of Contents

Supporting & Undermining Lesson

The lesson covers the types of supporting & undermining questions that show up on the Digital SAT.

What Do Supporting & Undermining Questions Look Like?

There are two types of supporting & undermining questions.

The first type of question will provide a long text, typically with background information in the beginning and a claim that is made toward the end of the text. The question will ask which piece of information either supports or undermines the claim.

The second type of question will provide one or two sentences, typically about a literary work. It will make a claim about that work and ask which excerpt (one of the answer choices) supports that claim.

Here are some examples of Supporting & Undermining questions from the Digital SAT.

  • Which finding, if true, would most directly undermine _______ ?
  • Which finding, if true, would most directly support _______ ?
  • Which finding, if true, would most strongly support _______ ?
  • Which finding from _______ , if true, would most directly weaken the claim made by _______?

How to Answer Supporting & Undermining Questions Correctly

  1. You’ll be asked to choose which detail would most support or undermine the author’s claim.
  2. Remember a support detail would strengthen a claim, and an undermining detail would weaken a claim.
  3. It is most important to identify the claim made by the author. Rewrite it in simpler language if it is complex.
  4. Considering what the claim is based on, think about what information would strengthen or weaken it before looking at the answer choices.

Tips for Supporting & Undermining Questions on the Digital SAT

Supporting details might be ones that:

  • Give another example that shows the claim is true
  • Show additional research that agrees

Undermining details could:

  • Give an example where a given condition was true, but the outcome was different
    • Example
      • Claim: Getting 8 hours of sleep or more improves test scores
      • Undermining detail: A group of students had 9 hours of sleep but performed worse on the tests than those who didn’t get 8 hours of sleep.
  • Give an example where the outcome was the same, but the given condition was different
    • Example
      • Claim: Getting 8 hours of sleep or more improves test scores
      • Undermining detail: A group of students that had 6 hours of sleep increased their test scores.
  • Show research that disagrees
  • Support the opposite of the claim

Example

Environmental scientist Priya Desai is studying a species of wetland plant that has spread rapidly throughout several marshes over the past decade. Desai observes that the plant grows especially densely in areas where water levels fluctuate frequently throughout the year. She hypothesizes that changing water levels help the species spread because many competing plants are less able to survive repeated flooding and drying cycles.

Which finding, if true, would most directly support Desai’s hypothesis?

A) Some wetlands containing the plant also experience unusually high nutrient levels in the soil.
B) Areas with the largest fluctuations in water levels tend to contain fewer competing plant species and the highest concentrations of the spreading plant.
C) Seeds of the plant can be carried long distances by birds migrating between wetlands across different regions each year.
D) Researchers studying wetland ecosystems have suggested that plant distribution patterns may be influenced by complex interactions involving soil chemistry, seasonal rainfall, insect populations, water temperature, erosion rates, and long-term environmental change.

Video Explanation

Text Explanation

Answer: B

If areas with fluctuating water levels contain fewer competing plants and more of the spreading species, that directly supports the hypothesis that changing water conditions reduce competition and allow the plant to spread rapidly.

Practice Problems with Video Explanations

Here is a set of practice Digital SAT supporting & undermining practice problems. After selecting an answer, press “See Answer” to see the correct answer and a video explanation showing how to properly solve the questions. At the end of the set, after you press “Submit”, you’ll be able to see all of the questions, answers, and video explanations to review.

For more practice like this, enroll in our on-demand SAT prep course here: https://caddellprep.com/sat/prep/on-demand/

1. Botanist Elena Ruiz studied a species of wildflower that grows on both windy coastal cliffs and in sheltered inland meadows. She observed that coastal plants tend to be shorter and produce thicker leaves than inland plants do. Ruiz hypothesizes that the cliff environment itself, rather than genetic differences between the two groups, causes these traits.

Which finding, if true, would most directly support Ruiz’s hypothesis?

Question 1 of 5

2. Historian Marcus Lee argues that a sharp decline in the use of a local port in the late 1700s was caused primarily by silting: over time, sediment made the harbor too shallow for large trading vessels. He notes that records from the period show reduced shipping traffic and lower customs revenue.

Which finding, if true, would most directly weaken Lee’s claim?

Question 2 of 5

3. Researchers studying an ancient settlement found that cooking pots near household hearths contain traces of lentils, barley, and goat milk. Because these residues appear in vessels from nearly every excavated ceremonial building, the researchers hypothesize that these foods were staples of the settlement’s daily diet rather than foods eaten only on special occasions.

Which finding, if true, would most directly support the researchers’ hypothesis?

Question 3 of 5

4. A literary scholar claims that a certain anonymous 19th-century essay was likely written by novelist Harriet Vale. The scholar bases this claim partly on the essay’s frequent use of long, winding sentences and ironic understatement, both features common in Vale’s confirmed works.

Which finding, if true, would most directly weaken the scholar’s claim?

Question 4 of 5

5. Marine biologist Tasha Green observed that a species of reef fish appears in greater numbers around coral formations with many narrow crevices than around smoother coral surfaces nearby. She hypothesizes that the fish prefer crevice-rich coral because those structures offer protection from predators.

Which finding, if true, would most directly support Green’s hypothesis?

Question 5 of 5


 

Related Topics

Fact and Graphs & Charts are topics related to Supporting & Undermining.

Fact

Supporting & undermining questions are related to fact questions because both require students to read the passage carefully. In fact questions, students need to identify what the text directly states. In supporting and undermining questions, students need to understand the facts in the passage before deciding which answer choice would strengthen or weaken the claim. Therefore, practicing fact questions can help students improve their ability to analyze evidence in supporting & undermining questions.

Graphs & Charts

Supporting & undermining questions are related to graphs & charts questions because both can require students to connect evidence to a claim. In some graphs & charts questions, students need to use data from a table, graph, or chart to determine which answer choice best supports an idea from the text. Supporting & undermining questions require a similar skill, except the evidence may come from an answer choice rather than a visual. Therefore, practicing graphs & charts questions can help students better understand how evidence supports or weakens a claim.

All Reading & Writing Topics

All of our reading & writing topics are available here: https://caddellprep.com/sat/reading-writing/ for you to review and improve on your SAT. There are lessons, practice problems, and video explanations for you. If you need more help, try our on-demand SAT course with video lessons, practice tests, and sets of questions for each topic: https://caddellprep.com/sat/prep/on-demand/

Glyn Caddell - Founder of Caddell Prep

Glyn Caddell

Glyn Caddell holds a BS in Mechanical Engineering from NJIT and has been tutoring New York City students since 2008. He founded Caddell Prep in 2012 and is the author of Digital SAT Math Secrets: Lessons & Tricks to Quickly Improve to a Perfect 800 on the Math Test, which contains over 900 practice problems and is used in Caddell Prep’s SAT math classes. He is founding president of the Staten Island Technical High School alumni association and teaches every lesson on this site personally.

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