RC Strengthen and Weaken: new facts against a passage's argument

Some Reading Comprehension questions hand you a new fact and ask whether it supports or undermines something in the passage. Stems read "which one of the following, if true, would most strengthen the author's argument" — the same wording you meet in Logical Reasoning, dropped into a passage twenty times longer.

The mechanics are identical to the LR version, so if you are solid there, you already know how to evaluate the choices. What is different, and what these questions actually test, is locating the argument.

Find the specific claim, not the passage's mood

A four-paragraph passage contains several arguments. The stem points at one — sometimes by naming it, sometimes by line reference, sometimes only by topic. Answering against the wrong one produces a confident wrong answer, and it is the single most common failure here.

So the first move is to go back and read the actual claim and its actual support, the way you would read a short LR stimulus. Two sentences, usually. Then work the choices against those two sentences and nothing else.

Then it's ordinary strengthen and weaken

Once the argument is isolated, the same things work: find the gap between evidence and conclusion, and ask whether the new fact widens or narrows it. Strengtheners often rule out an alternative explanation; weakeners often supply one.

• Aimed at the wrong argument. Genuinely strengthens something the passage says, just not the claim the stem named.
• Restates passage evidence. Adds nothing new, and support has to be new to be support.
• Affects the topic, not the reasoning. Interesting, on-subject, and leaves the gap exactly where it was.
• Backwards. Strengthens on a weaken question — always present, and easy to grab when reading fast.
• Attacks a claim the author never made, usually a stronger version of their actual position.

One habit covers most of it: before reading the answers, say the targeted argument out loud in two sentences — this is the claim, this is the support. If you cannot, you have not found the argument yet, and no amount of care with the choices will rescue that.