Command of Evidence
Command-of-evidence questions test whether you can pick the data point that *most directly proves* a claim — not the one that's merely related to it.
Command of evidence comes in two flavors:
1. Textual evidence. Given a claim, pick the passage quote that best supports it.
2. Quantitative evidence. Given a researcher's claim, pick the row from a table or graph that would support it if true.
Both types share the same trap: the wrong answers are usually true facts that don't support the specific claim. Your job is to be a strict logician — only the choice that directly proves this claim is correct.
| Claim | Candidate fact | Counts? |
|---|---|---|
| 8+ hour sleepers score higher than <6 hour sleepers on math | 8+ scored 78; <6 scored 64 | ✓ Yes — exact group + metric match |
| 8+ hour sleepers score higher than <6 hour sleepers on math | 60% of students slept 7-8 hours | ✗ No — sample fact, not score comparison |
| Adichie uses food imagery to show emotional distance | Soup goes cold while characters don't speak | ✓ Yes — food + distance both shown |
| Adichie uses food imagery to show emotional distance | The market was loud and colorful | ✗ No — food-adjacent, but not about distance |
The technique:
- Read the claim carefully. Underline the specific part being claimed (not the general topic).
- Look at each choice and ask: "if this is true, does it follow that the claim is also true?"
- Eliminate choices that are true but don't prove the claim.
Example mismatch: Claim: "Daily exercise improves test scores in middle schoolers." Wrong evidence: "Adults who exercise daily report higher mood." True, related — but doesn't support the specific claim about middle schoolers and test scores.
For quantitative questions: read the table's column headers and units carefully. The right row is usually the exact comparison the claim implies. If the claim says "X is higher in group A than B," find the row showing A > B in the X column. Don't get distracted by other interesting rows.
Pause and check yourself. Read the claim, then ask of each choice: *if this is true, does it follow that the claim is true?* Eliminate the merely-true-but-unrelated.
In her 1892 address to the National American Woman Suffrage Association, Elizabeth Cady Stanton argued that the right to vote was not merely a political convenience but a fundamental expression of individual sovereignty. "The strongest reason for giving woman all the opportunities for higher education, for the full development of her faculties," she declared, "is the solitude and personal responsibility of her own individual life."
Which quotation from the passage most directly supports Stanton's argument that voting rights are connected to personal autonomy?
Worked examples
A researcher claims: "Students who slept 8+ hours scored higher on math tests than students who slept fewer than 6 hours."
Which choice from a study's data table would best support that claim?
A literary critic argues: "In her novel, Adichie uses food imagery to convey emotional distance between characters."
Which quote from the novel best supports this claim?
Common pitfalls
Wrong choices are often genuine facts from the passage. They just don't support the specific claim. A general fact about the topic is not evidence for a specific assertion.
If a quote feels like it goes with the claim — same theme, same characters — it's tempting. But the test asks you to be strict: does this prove the claim? If you'd need extra steps to connect them, it doesn't.
If the claim is about rate per 100 people and the choice gives total count, those aren't comparable. Read the table's headers, units, and group labels carefully.
When a claim has multiple parts (X uses Y to convey Z), the right evidence covers ALL parts. Half-support is wrong support.
Key takeaways
Evidence questions reward strict logic: the choice has to prove the claim, not just relate to it.
Wrong answers are usually true facts that miss the specific point.
On quantitative questions, match the exact groups, metric, and units the claim names.
If the claim has multiple parts, the right answer covers all of them.
Predict what evidence should look like before reading the choices.
Watch & learn
Curated Khan Academy walkthroughs on Command of Evidence. They're complementary to this lesson — watch one if a written explanation isn't clicking, or after to reinforce.
Try it yourself
5 practice questions on Command of Evidence, drawn from the question bank. The tutor is one click away if you get stuck.