The stem tells you exactly what to do
Three wordings cover almost every item in this family.
“Which finding, if true, would most strongly support the researchers' hypothesis?”
“… would most directly weaken the argument?”
“Which quotation from the text most effectively illustrates the claim?”
The phrase if true matters. You are not asked whether the finding is real, nor whether it is
stated in the passage. You are asked what would follow if it were so.
The first move is never to read the choices. It is to compress the claim into one conditional sentence, in your own words:
Claim: the ants navigate by counting steps.
Conditional: if that is so, then changing the length of an ant's stride should change where
it stops.
Now each choice is measured against a prediction, not against a vague sense of relevance.
Which finding, if true, would most strongly support the researchers' hypothesis?
- Ants whose legs were lengthened walked past the nest, and ants whose legs were shortened stopped short of it.
- Ants released in unfamiliar terrain still set off in the correct compass direction.
- Ants whose legs were lengthened reached the nest as accurately as untreated ants.
- Ants took longer to return to the nest than they had taken to leave it.
The conditional says: change the stride, and the ant should misjudge the distance in a predictable direction. (A) is that prediction, and both halves of it point the same way. (C) is the outcome that would sink the hypothesis. (B) concerns direction, not distance — a different navigation question. (D) has no bearing on either. Answer (A).
Bước ép nhận định thành câu “nếu… thì…” nghe có vẻ tốn thời gian nhưng thực ra tiết kiệm. Không có câu đó, bốn phương án đều “liên quan tới chủ đề” và học sinh phải cân nhắc cả bốn. Có nó rồi, ba phương án bị loại trong vài giây vì chúng nói về một đại lượng khác hẳn.
Support is not the same as “does not contradict”
Most wrong choices in this family are compatible with the claim. Compatibility is worthless: a finding supports a claim only if it would be less likely were the claim false.
The discrimination test. Ask: would this finding also be true if the rival explanation were the correct one? If yes, it supports nothing. The right answer is the one that fits the claim and does not fit its rival.
Which finding, if true, would most strongly support the geologist's argument?
- The boulders' surfaces bear sets of parallel scratches of the kind produced by grinding under ice.
- The boulders are far larger than the present-day stream could move.
- The valley floor beneath the boulders consists of well-sorted gravel graded from coarse to fine.
- The boulders are of a rock type that outcrops only two hundred kilometres up the valley.
(B) and (D) are both true of glacier transport — and equally true of a flood, which is precisely why they decide nothing. (C) points the other way: sorting by size is what moving water does, and ice does not sort. Only (A) is expected under ice and not under water. Answer (A).
Phương án “ấn tượng nhất” thường là phương án không phân biệt được hai giả thuyết. Tảng đá to hơn sức dòng suối hiện tại nghe rất thuyết phục — nhưng lũ quét cũng khiêng được tảng đá to. Câu hỏi đúng không phải “cái này có hợp với giả thuyết không” mà là “cái này có loại được giả thuyết đối thủ không”.
The same test settles support items that set two named causes against each other: look for the choice that switches one cause off and leaves the other running.
Which finding, if true, would most strongly support the conservator's proposal?
- Areas covered by a later altarpiece for two centuries, which shielded them from light but not from air, have faded as much as the exposed areas.
- Laboratory tests show that the pigment fades rapidly under strong illumination.
- The fresco was cleaned in 1954 with a solvent now known to be harsh.
- The city's air quality has been monitored continuously since 1970.
(A) separates the two candidates: light was removed, air was not, and the fading happened anyway. (B) supports the explanation the conservator rejects. (C) offers a third cause and so weakens. (D) is administrative background. Answer (A).
Weakening a causal claim
When a passage moves from a correlation to a cause, there are exactly three places to attack, and the test uses all three.
- A third factor. Something else produced both the supposed cause and the effect.
- Reversed direction. The effect came first and produced the “cause”.
- No effect to explain. The change would have happened anyway, or the measurement changed rather than the world.
Which finding, if true, would most directly weaken the author's conclusion?
- Every school in the sample charged a fee for instrument lessons, and family income predicted both instrument-playing and mathematics scores.
- Some students who scored highly in mathematics did not play any instrument.
- The mathematics advantage was larger among students who had played for more years.
- Instrument lessons at the schools took place outside timetabled hours.
(A) supplies a third factor that generates the correlation without any causal link. (C) is the pattern the author's claim predicts, so it strengthens. (B) is expected under the claim as well — the claim is about averages, not about every individual. (D) is a fact about scheduling. Answer (A).
Which finding, if true, would most directly weaken the researcher's argument?
- The species planted grow slowly and cast almost no shade for their first decade, and the fall in visits appeared in the first two summers.
- Residents surveyed after the planting said they liked having the trees.
- Neighbourhoods that received no trees showed no change in heat-illness visits.
- The programme planted more trees than had originally been budgeted for.
(A) attacks the mechanism: whatever caused the fall, it cannot have been shade that did not yet exist. (C) is a control result that supports the argument. (B) and (D) are about the programme's reception and size. Answer (A).
Cẩn thận với phương án dạng “vùng không tham gia chương trình thì không thay đổi”. Đọc nhanh dễ thấy nó “liên quan tới việc so sánh” rồi chọn khi đề hỏi làm suy yếu — nhưng đó chính là nhóm đối chứng, và nhóm đối chứng không đổi là bằng chứng ủng hộ. Luôn đọc lại lệnh hỏi là support hay weaken ngay trước khi bấm chọn.
Attacking the measurement, not the world
A large share of hard items turn on a change in how something was counted. The effect is real in the data and absent in reality. Nothing about the world has to change for a recorded number to move: it is enough that the definition, the instrument or the cost of reporting changed at the same moment as the supposed cause.
Which finding, if true, would most directly weaken the council's argument?
- The programme replaced a telephone reporting line, open at all hours, with an online form that refuses any report submitted more than seventy-two hours after the event.
- The programme cost less than the council had originally budgeted for it.
- Households in the district were offered free window locks as part of the programme.
- Neighbouring districts, which ran no such programme, recorded no change in burglaries over the same year.
(A) changes what gets into the record without changing what happens in the street: late reports that the old line accepted now vanish, and a quarter of the burglaries may simply have gone uncounted. (D) is the control result, and a control that stays flat while the treated district improves supports the council. (C) is part of the programme and, if anything, helps its case. (B) is about money. Answer (A).
Ba đòn đánh một nhận định nhân quả nên học thuộc theo thứ tự dò: có yếu tố thứ ba nào sinh ra cả hai vế không; chiều nhân quả có thể ngược lại không; và “hiệu ứng” đó có thật hay chỉ là cách đo thay đổi. Gần như mọi câu weaken khó của SAT rơi vào một trong ba, và đòn thứ ba là đòn học sinh Việt Nam hay bỏ sót nhất.
The literary version: illustrate the claim
With fiction, poetry and memoir the stem asks which quotation illustrates a claim. The answer must contain the thing claimed, not merely the topic of the claim. A quotation that states what a character says about himself almost never illustrates a claim about what he actually does.
Which quotation from the novel most effectively illustrates the underlying claim?
- “The house was cold that winter, and she kept the fire low to save coal.”
- “`I bear him no grudge,' she said, and turned his photograph face down as she passed.”
- “Her brother had left the town in the spring of 1912 and had not come back.”
- “She forgave him, and the forgiving cost her a great deal.”
The claim has two parts: she says she has forgiven him, and the text shows otherwise. Only (B) contains both — the declaration and the gesture that contradicts it. (D) contains the first part and confirms rather than undercuts it. (C) is background and (A) is unrelated. Answer (B).
Ở dạng trích dẫn văn học, phương án dài nhất và giàu hình ảnh nhất rất hay là nhiễu. Tiêu chí duy nhất là: bỏ câu trích này đi thì nhận định có mất chỗ dựa không. Câu văn hay nhưng không chứa đúng thứ được khẳng định thì vô dụng.