A student notes question with a two-part goal tests whether you can write a sentence that does both jobs. Read the goal first, and list every demand to see what the answer needs to do. For an experiment, ask what the setup rules out and what it leaves uncertain. Cross out sentences that miss either job, even if their facts are true. Then check every claim against the notes, since meeting the goal doesn’t make an added claim true.
Hints
- Hint 1
The goal contains two jobs joined by “while also.” Separate the two jobs so you can test each one.
- Hint 2
Look at how the pots, roots, and airflow were handled. Check what stayed the same and what changed between the air treatments.
- Hint 3
Compare what the filter removes with the hypothesis. Does the filter test methyl jasmonate separately from the other compounds it removes?
Step-by-step
Separate the route from the compound
Step 1Name both demands
Read the goal’s two parts: airborne signaling over belowground signaling and why the result doesn’t establish that methyl jasmonate specifically caused the response. What does the answer need to cover? The answer needs support for how the signal travels and a limit on naming the compound. The endings when plants share soil and travel through shared soil discuss soil signaling instead of the required limit on methyl jasmonate’s role.
- Step 2
See what the setup rules out
The soil and roots were enclosed to prevent belowground exchange, so signals couldn’t pass between these plants through soil. What changed their defenses? Plants receiving unfiltered air increased their defensive chemicals, whereas plants receiving filtered air did not. With airflow, light, and temperature held the same, removing airborne compounds changed the response, which supports an airborne cause in this experiment.
- Step 3
Identify what the filter can’t show
How much can we learn about methyl jasmonate? Activated carbon removes many airborne compounds, including methyl jasmonate. The response could depend on methyl jasmonate, another removed compound, or a mixture, and the result would look the same in each case. So methyl jasmonate’s role remains unproven, because the filter didn’t change that compound separately from the others.
- Step 4
Check what each claim assumes
Does either remaining choice assume that methyl jasmonate specifically caused the response? The phrase methyl jasmonate acted alone or in combination with them assumes the compound took part, leaving open only whether it acted alone. The sentence saying an airborne rather than belowground cause doesn’t assume methyl jasmonate was involved, and it uses the filter’s removal of many compounds to explain that limit. Choice B.