For SAT Reading & Writing inference completion questions, restate the key facts (especially comparisons and results), then choose the option that makes a cautious conclusion that stays within the evidence. Be skeptical of extreme words (always, never, entirely, completely) and of prescriptive policy claims (must, should require) that were not tested. Eliminate choices that introduce new assumptions or single-cause explanations not supported by the text.
Hints
- Hint 1
Focus on the comparison
Look closely at how the results of group (a) compare to the results of group (b). What did group (a) get that group (b) did not?
- Hint 2
Watch for extreme wording
Check each answer for words like "ineffective," "entirely," or strong recommendations like "should require." Ask if the study’s data is strong enough to support those extremes.
- Hint 3
Stick to what the study actually tested
The study only compared two specific setups over 12 months. Avoid choices that make broad claims about all causes or that dictate exact policies the city must follow.
- Hint 4
Match the scope of the conclusion to the data
Look for an option that reflects that one approach led to better composting results than the other, without making claims that go beyond that evidence.
Step-by-step
- Step 1
Restate what the study did
First, summarize the setup:
- 20 neighborhoods were put into two groups.
- Group (a) got free curbside compost bins plus optional monthly workshops.
- Group (b) got mailed instructions about how to compost and where to buy bins. The question asks what is most reasonable to infer based on these results.
- Step 2
Restate the main findings
Now restate the outcomes:
- After 12 months, group (a) diverted 35% more food scraps from landfill than group (b).
- Group (a) also had lower contamination in compost bins. So the group that got both bins and workshops had better composting outcomes than the group that only got mailed instructions.
- Step 3
Decide what kind of conclusion is reasonable
We must choose a statement that:
- Matches the comparison: group (a) vs. group (b).
- Uses moderate language (not absolute claims like "completely ineffective" or "entirely caused").
- Does not overreach into policy rules (like what the city “should require”) that the study did not test. We are looking for an option that reflects that the group (a) approach led to better results than group (b).
- Step 4
Check each answer choice against the evidence
Evaluate the options:
- Choice B says mailed instructions alone are completely ineffective. But the study only shows they were less effective than bins plus workshops; it does not show they had no effect.
- Choice C says the city should require workshops before giving bins. The study tested optional workshops and does not compare required vs. optional attendance, so this is too prescriptive.
- Choice D says contamination is caused entirely by lack of information. The study never rules out other causes; it only reports lower contamination in group (a).
- Choice A states that providing free bins and optional workshops can substantially improve composting outcomes, which matches the study’s results without overclaiming.
Therefore, the correct answer is: providing free compost bins and optional workshops can substantially improve composting outcomes.