SAT Reading & Writing · Information and Ideas

Central Ideas & DetailsHow the SAT tests it — and how to beat it

Identifying a passage's main idea and locating the specific details that support it — the core reading-comprehension skill on the SAT.

Practice Central Ideas & Details Free All of Information and Ideas

Central Ideas & Details in Our Question Bank

Total questions

Easy

Medium

Hard

What the SAT Actually Tests

These questions ask for a passage's main idea or a specific stated detail. On the digital SAT each passage is short (25-150 words), so the skill is precision: the right answer restates what the text says, and every wrong answer distorts it slightly — too broad, too narrow, or subtly off-topic.

Read the passage first and formulate the main point in your own words before touching the choices — then find the match. For detail questions, physically locate the sentence containing the answer; if you can't point to it, you're inferring, and these questions never require inference. Eliminate any choice using extreme language the passage doesn't use.

Real Central Ideas & Details Practice Questions

Straight from the Grind1600 question bank — try each one before revealing the answer.

Question 1easy

Marine biologist Keiko Tanaka spent over a decade studying coral reefs in the Pacific Ocean. She noticed that reefs near coastal cities showed more signs of bleaching than reefs farther from human settlements. Tanaka concluded that pollution from urban runoff was a major contributor to coral stress. She recommended that cities near reef systems invest in better water filtration to reduce the amount of harmful chemicals entering the ocean. According to the text, what did Tanaka conclude was a major cause of coral stress?

A)Rising ocean temperatures caused by global climate patterns.
B)Natural predators that feed on weakened coral.
C)Overfishing in areas surrounding coral reefs.
D)Pollution from urban runoff near coastal cities.

Show answer & explanation

Correct answer: D

Choice D is the best answer because the text directly states that Tanaka 'concluded that pollution from urban runoff was a major contributor to coral stress.' Choices A, B, and C are incorrect because the text does not mention rising ocean temperatures, natural predators, or overfishing as causes of coral stress.

Question 2medium

In the early twentieth century, the Argentine writer Jorge Luis Borges became fascinated with the concept of infinite libraries. His short story "The Library of Babel" imagines a universe composed entirely of hexagonal rooms filled with books containing every possible combination of characters. While the story is often read as a meditation on the nature of meaning and language, literary scholar María Elena Walsh has argued that Borges was primarily concerned with the psychological toll of limitless information. Walsh points to Borges's personal letters, in which he frequently expressed anxiety about the growing volume of published works and his inability to read them all within a single lifetime. Which choice best states the main idea of the text?

A)Borges's "The Library of Babel" is widely considered to be his most important contribution to world literature.
B)Borges wrote "The Library of Babel" specifically to warn readers about the dangers of publishing too many books.
C)María Elena Walsh discovered previously unknown letters written by Borges that changed how scholars interpret his fiction.
D)While Borges's story is commonly interpreted as being about language, one scholar suggests it more centrally reflects concerns about information overload.

Show answer & explanation

Correct answer: D

Choice D is the best answer. The text first gives the common reading of "The Library of Babel" as a meditation on meaning and language, then presents Walsh's argument that Borges was "primarily concerned with the psychological toll of limitless information," citing his personal letters. Choice D captures both halves of that structure.

Choice A is incorrect. The text doesn't rank the story among Borges's works or assess its importance to world literature.

Choice B is incorrect. This distorts Walsh's reading. The concern the text describes is the psychological toll of limitless information, not a warning about publishing too many books.

Choice C is incorrect. The text says Walsh points to Borges's personal letters, but never says she discovered previously unknown ones or that her work changed how scholars interpret his fiction.

Traps to Avoid

Choosing an answer that's true in the real world but not stated in the passage.
Picking a choice that captures one detail of the passage as if it were the main idea.
Falling for answers that reuse the passage's exact words while changing the meaning.

More Information and Ideas Skills

Command of Evidence (Textual)

Choosing the quotation or finding that most directly supports, illustrates, or weakens a stated claim or hypothesis.

Command of Evidence (Quantitative)

Using data from tables and graphs to complete or support a passage's argument — reading the graphic precisely is the whole game.

Inferences

Selecting the statement that most logically completes a passage's reasoning — strictly bounded by what the text actually establishes.

Master Central Ideas & Details With Adaptive Practice

47 Central Ideas & Details questions with step-by-step explanations, woven into a day-by-day study plan built for your test date.

Get Started Free

What the SAT Actually Tests

Real Central Ideas & Details Practice Questions

Straight from the Grind1600 question bank — try each one before revealing the answer.

Question 1easy

A)Rising ocean temperatures caused by global climate patterns.
B)Natural predators that feed on weakened coral.
C)Overfishing in areas surrounding coral reefs.
D)Pollution from urban runoff near coastal cities.

Show answer & explanation

Correct answer: D

Question 2medium

A)Borges's "The Library of Babel" is widely considered to be his most important contribution to world literature.
B)Borges wrote "The Library of Babel" specifically to warn readers about the dangers of publishing too many books.
C)María Elena Walsh discovered previously unknown letters written by Borges that changed how scholars interpret his fiction.
D)While Borges's story is commonly interpreted as being about language, one scholar suggests it more centrally reflects concerns about information overload.

Show answer & explanation

Correct answer: D

Choice A is incorrect. The text doesn't rank the story among Borges's works or assess its importance to world literature.

Choice B is incorrect. This distorts Walsh's reading. The concern the text describes is the psychological toll of limitless information, not a warning about publishing too many books.

Choice C is incorrect. The text says Walsh points to Borges's personal letters, but never says she discovered previously unknown ones or that her work changed how scholars interpret his fiction.