#15 · All four are true? Split the claim.
The question. In a greenhouse experiment, a student grew one group of bean plants with a new fertilizer and another group without it. After eight weeks, the student measured each plant's height and counted its pods. The student concluded that plants grown with the fertilizer were taller but produced fewer pods than plants grown without it.
The question shows two bar graphs, one for each measure. Their values:
| Without fertilizer | With fertilizer | |
|---|---|---|
| Average height (cm) | 12 | 18 |
| Average pods per plant | 9 | 6 |
Which choice most effectively uses data from the graphs to support the student's conclusion?
- Plants grown with the fertilizer had an average height of 18 cm, while plants grown without it had an average height of 12 cm.
- Plants grown with the fertilizer averaged 6 pods per plant, while plants grown without it averaged 9 pods per plant.
- Plants grown with the fertilizer averaged 18 cm in height and 6 pods per plant, while plants grown without it averaged 12 cm and 9 pods.
- Plants grown without the fertilizer had an average height of 12 cm and averaged 9 pods per plant.
The catch. Every choice reads the graphs correctly. So "Is it true?" can't pick the answer. The question is which choice supports the conclusion.
The move: split the claim. Before you read the choices, break the conclusion into its parts. This one makes two claims about the plants grown with the fertilizer, each compared with the plants grown without it:
- They were taller.
- They produced fewer pods.
The right answer has to support both.
Use it.
- A compares the heights of the two groups. True, but it supports only part 1.
- B compares the pods. True, but it supports only part 2.
- C gives both groups on both measures: 18 cm against 12 cm (taller) and 6 pods against 9 (fewer). It supports both parts, so the answer is C.
The same check on other data questions
When a question asks which choice uses data to support a claim, a choice can describe the graph accurately and still be wrong. Check each one against the claim:
- Does it support every part of the claim?
- Does it compare the same groups the claim compares?
- Does it use the same measure, and the same year or place if the claim names one?
The takeaway: split the claim. Every part needs evidence. Cross out any choice that leaves a part unsupported, even if every word of it is true.