Question 41·Medium·Inferences
It’s often claimed that talking to houseplants helps them thrive, but whether any benefit comes from what is said or from the sound itself is unclear. To test this, a team led by botanist Lila Mendes raised genetically identical pothos cuttings for eight weeks under identical light and watering but different sound conditions: silence, recorded passages read in English, recorded strings of nonsense syllables read with the same tone and pacing, and recorded wind noise. All recordings were played at the same average volume. Plants exposed to English and to nonsense syllables showed similar increases in total leaf area compared with plants in silence, while the wind-noise group did not differ from the silent group, suggesting that _____
Which choice most logically completes the text?
For "suggesting that" completion questions in science passages, first summarize the experimental setup: what changed (independent variable) and what was measured (result). Then restate the pattern of results in your own words. Next, eliminate any choice that contradicts the data, says something the experiment didn’t test, or goes beyond what the evidence can support (like claiming plants "understand" language). Finally, pick the choice that most directly and conservatively restates what the results imply, focusing on what the successful conditions have in common and how they differ from the unsuccessful ones.
Hints
Locate the evidence for the conclusion
Focus on the sentence that begins "Plants exposed to English and to nonsense syllables showed similar increases…" and note how each sound condition compares with silence.
Compare which sounds helped and which did not
Ask yourself: Which groups grew more than the silent group? Which group showed no difference from silence? What does that pattern rule out?
Think about meaning vs type of sound
English passages have meaningful words, while nonsense syllables do not. Yet they produced similar growth. What do those two recordings still have in common that wind noise does not share?
Step-by-step Explanation
Understand the experiment setup
The researcher grew genetically identical pothos cuttings for eight weeks. All plants had the same light, watering, and sound volume, but there were four different sound conditions:
- silence
- recorded English passages
- recorded nonsense syllables (same tone and pacing as the English)
- recorded wind noise
Only the type of sound changed; everything else was controlled.
Interpret the key results
We are told that plants exposed to English and nonsense syllables had similar increases in total leaf area compared with plants in silence. The wind-noise group did not differ from the silent group.
So:
- English speech: more growth than silence.
- Nonsense speech: more growth than silence.
- Wind noise: about the same as silence.
Figure out what the pattern implies
English and nonsense recordings both helped growth, even though one has meaningful words and the other does not. This suggests that the meaning of the words is not what matters. At the same time, both English and nonsense are examples of human speech sounds, while wind noise is not, and wind noise gave no benefit. So whatever is helping must be something that English and nonsense speech share and wind noise lacks.
Match the implication to the best choice
The conclusion should say that something about the sound qualities shared by human speech (like rhythm, tone, or other acoustic features), rather than the meaning of the words, seems to promote pothos growth. Choice A) some acoustic features common to human speech, rather than the meaning of the words, may promote pothos growth. states exactly that idea and fits the results, so A is the correct answer.