Summarizing Key Supporting Ideas

A summary is not the passage with words removed. It is the passage's shape: the few ideas everything else hangs from, plus how those ideas relate to each other. Every passage has supporting ideas doing real structural work, like a cause, a result, a contrast, or a sequence, and then has facts, numbers, and examples that just decorate that structure. A correct summary choice keeps the structure and throws out the decoration. A wrong one usually does the opposite: it keeps a vivid fact and loses the relationship that fact was there to support.

This is why the longest answer choice is rarely the best one. Length comes from detail, and detail is exactly what a summary is supposed to compress. A long choice that restates numbers, names, or examples from the passage is doing the job of a highlighter, not a summary. The correct choice is often short precisely because it has already done the compressing: it names the mechanism, the cause-and-effect, or the pattern, and leaves the supporting evidence behind in the passage where it belongs.

This topic sits right next to finding the central idea and distinguishing a theme from a lesson. Central idea asks what single claim the passage is built around; summarizing asks you to compress the whole argument, including its supporting moves, into a sentence or two without breaking its logic. If a summary keeps every fact but scrambles the order events happened in, or drops which thing caused which, it stops being a summary and becomes a list, even if nothing in it is technically false.