command of evidence

Every Command‑of‑Evidence item asks a single question: “How do you know?” There's two types of these questions: textual and quantitative. We're gonna go over both.

1. Textual

The SAT splits these questions into two domains:

Scientific

Validate or refute a hypothesis. Look for measurable results that align with the prediction.

Question types include:

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

Which finding, if true, would most directly support the researchers' claim?

Literary

Pick the quotation that directly illustrates the stated interpretation of a text.

Question types include:

Which quotation from the text most effectively illustrates the claim?

Which statement, if true, would most strongly support the claim in the underlined sentence?

Passage Excerpt

Elena moved through the orchard as if retracing a forgotten map, her hand brushing the low branches that once shaded their summer stories. Though the air was still, she paused as if listening—listening for the echo of her father’s voice in the hush between leaf and limb. Each apple underfoot seemed to hum with memory, and when she stooped to collect one, it was with the careful reverence of someone lifting a relic.

Question: A student claims that the author uses the orchard setting to highlight Elena’s deep emotional bond with her father. Which quotation from the passage most effectively illustrates this claim?

A) “Elena moved through the orchard as if retracing a forgotten map…”
B) “Her hand brushing the low branches that once shaded their summer stories.”
C) “She paused as if listening—listening for the echo of her father’s voice in the hush between leaf and limb.”
D) “Each apple underfoot seemed to hum with memory…”

Show Correct Answer

Correct Answer: C) “She paused as if listening—listening for the echo of her father’s voice in the hush between leaf and limb.”

Explanation:This line most clearly connects Elena’s emotional state to the setting. Her action of pausing and “listening for the echo” of her father’s voice shows how the orchard is filled with personal, emotional meaning. Other choices suggest nostalgia or memory, but only C directly illustrates the student’s claim of a lasting emotional bond reflected in the setting.

2. Quantitative

A graph or table accompanies a short blurb. Choose the statement best supported by the numbers.

Types of quantitative questions include:

- Which choice most effectively uses data from the graph/table to complete the statement? - Which choice best describes data in the graph that support the team’s conclusion?

Passage & Data

A research team studying urban commuting patterns concluded that implementing bike lanes significantly reduces average commute times in cities with high traffic congestion. The team collected data from six cities before and after installing protected bike lanes.

City	Avg. Commute Time (Before)	Avg. Commute Time (After)
Metroville	47 min	41 min
Iron City	39 min	38 min
Grandport	45 min	40 min
Eastbridge	51 min	46 min
Rosemont	36 min	35 min
Baytown	50 min	44 min

Question: Which choice best describes data in the graph that support the team’s conclusion?

A) All cities saw the same reduction in commute times regardless of original congestion level.
B) Cities with longer original commutes generally experienced larger time reductions after installing bike lanes.
C) Bike lanes had minimal impact on overall commute times, particularly in cities with high congestion.
D) Commute times decreased only in cities where bike lanes replaced major highways.

Show Correct Answer

Correct Answer: B) Cities with longer original commutes generally experienced larger time reductions after installing bike lanes.

Explanation:The data shows that cities like Metroville, Eastbridge, Grandport, and Baytown — all with initial commute times above 45 minutes — saw reductions of 5–6 minutes. In contrast, Iron City and Rosemont had shorter original commutes and saw smaller improvements. This supports the idea that bike lanes help most where congestion is already high.

common traps

Buzzword bait: shares vocab, lacks proof.
Too general: feels true but not specific.
Off‑scope: wrong subject or timeframe.
Graph slip: swap axes or ignore units.

Let's try some practice problems from the College Board Practice Bank, that aren't on the Bluebook Practice Tests.

Question 1

Although many transposons, DNA sequences that move within an organism’s genome through shuffling or duplication, have become corrupted and inactive over time, those from the long interspersed nuclear elements (LINE) family appear to remain active in the genomes of some species. In humans, they are functionally important within the hippocampus, a brain structure that supports complex cognitive processes. When the results of molecular analysis of two species of octopus—an animal known for its intelligence—were announced in 2022, the confirmation of a LINE transposon in Octopus vulgaris and Octopus bimaculoides genomes prompted researchers to hypothesize that that transposon family is tied to a species’ capacity for advanced cognition.

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

Question 2

Nucleobase Concentrations from Murchison Meteorite and Soil Samples (ppb)

Nucleobase	Meteorite 1	Meteorite 2	Soil
Isoguanine	0.5	0.04	not detected
Purine	0.2	0.02	not detected
Xanthine	39	3	1
Adenine	15	1	40
Hypoxanthine	24	1	2

Employing high-performance liquid chromatography—a process that uses pressurized water to separate material into its component molecules—astrochemist Yashiro Oba and colleagues analyzed two samples of the Murchison meteorite that landed in Australia as well as soil from the landing zone of the meteorite to determine the concentrations of various organic molecules. By comparing the relative concentrations of types of molecules known as nucleobases in the Murchison meteorite with those in the soil, the team concluded that there is evidence that the nucleobases in the Murchison meteorite formed in space and are not the result of contamination on Earth.

Which choice best describes data from the table that support the team’s conclusion?

Question 3

In 1534 CE, King Henry VIII of England split with the Catholic Church and declared himself head of the Church of England, in part because Pope Clement VII refused to annul his marriage to Catherine of Aragon. Two years later, Henry VIII introduced a policy titled the Dissolution of the Monasteries that by 1540 had resulted in the closure of all Catholic monasteries in England and the confiscation of their estates. Some historians assert that the enactment of the policy was primarily motivated by perceived financial opportunities.

Which quotation from a scholarly article best supports the assertion of the historians mentioned in the text?

✓

Command of Evidence Mastered

You can now dissect every DSAT evidence prompt—with receipts.

Next Up

15: text structure and purpose

Level‑up on seeing how authors build their arguments.