ACT® · Science: Evaluating Scientific Arguments and Models with Evidence (8-13 items)
Whether Information Supports or Contradicts a Hypothesis, and Why (EMI 502 and 702)
Every support-or-contradict question on the science test has two parts: the yes-or-no call, and the specific number or trend that proves it. Answer choices test whether you paired them correctly.
A claim makes a specific, checkable promise: levels stay under some value, a reaction finishes by some time, a trend moves in some direction. Your job is to find the one piece of data in the table or figure that actually tests that promise, then decide if it fits. The verdict alone is never the answer. The test wants the verdict glued to the number that justifies it, because a student who guesses the right yes-or-no by luck hasn't shown they read the data.
Answer choices are usually built on a four-way grid: supports because (right verdict, right reason), supports but (right verdict, wrong or irrelevant reason), contradicts because, and contradicts but. The wrong-reason traps are the dangerous ones. They often cite a real number from the table, just not the number that matters, or they describe the data backwards. You eliminate them by checking whether the stated reason, read on its own, actually forces the verdict given.
This matters because the whole unit is about treating a hypothesis like a claim on trial: you read a model, find what it predicts, and test that prediction against the data rather than against your general science knowledge. When the evidence is a single reading, the reason is that number's distance from the claim's limit. When the evidence is a trend across several points, the reason has to describe the direction of change across all of them, since any single point can look fine while the pattern contradicts the claim.
Key terms
- Claim
- A specific, checkable statement a hypothesis or model makes, such as a limit, a timeframe, or a direction of change.
- Verdict
- The yes-or-no call on whether the data supports or contradicts the claim.
- Supports but / Contradicts but
- A trap answer choice that pairs the correct verdict with an irrelevant or incorrect reason.
- Trend evidence
- Data given across multiple points where the reasoning must describe the direction of change, not any single value.
Watch it explained
- How it worksHow do you pair a yes-or-no verdict with the single number that actually justifies it?
- How it worksWalk me through a four-way answer grid: supports because, supports but, contradicts because, contradicts but.
- Worked exampleFind whether a reading of 4.2 ppm supports a claim that levels stay under 4.0 ppm, and say why.
- Common mistakeWhy isn't a correct verdict with a wrong reason ever a correct answer on ACT Science?
- Going furtherWhat changes about the reasoning half of an answer when the evidence is a trend rather than one value?
Check yourself
End of topic.