Plants like potatoes, tomatoes, and soybeans are susceptible to bacterial wilt disease caused by the bacteria Ralstonia solanacearum. A multinational...
GMAT Information and Ideas : (Ideas) Questions
Plants like potatoes, tomatoes, and soybeans are susceptible to bacterial wilt disease caused by the bacteria Ralstonia solanacearum. A multinational team of scientists led by Zhong Wei studied whether other microbes in the soil might influence the degree to which plants are affected by the disease. The team sampled soil surrounding individual tomato plants over time and compared the results of plants that became diseased with those that remained healthy. They concluded that the presence of certain microbes in the soil might explain the difference between healthy and diseased plants.
Which finding, if true, would most directly support the team's conclusion?
The soil surrounding healthy plants contained significantly higher concentrations of microbes known to inhibit Ralstonia solanacearum than the soil surrounding diseased plants did.
The soil surrounding the plants contained high concentrations of Ralstonia solanacearum regardless of whether the plants were affected by wilt disease.
The soil surrounding healthy plants tended to have significantly higher moisture levels than the soil surrounding diseased plants did.
By the end of the experiment, over half the plants had been affected by wilt disease regardless of differences in the types and concentrations of microbes in the surrounding soil.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Plants like potatoes, tomatoes, and soybeans are susceptible to bacterial wilt disease caused by the bacteria Ralstonia solanacearum." |
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| "A multinational team of scientists led by Zhong Wei studied whether other microbes in the soil might influence the degree to which plants are affected by the disease." |
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| "The team sampled soil surrounding individual tomato plants over time and compared the results of plants that became diseased with those that remained healthy." |
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| "They concluded that the presence of certain microbes in the soil might explain the difference between healthy and diseased plants." |
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Part B: Provide Passage Architecture & Core Elements
Main Point: Researchers concluded that certain soil microbes might explain why some plants stay healthy while others get bacterial wilt disease.
Step 2: Interpret the Question Precisely
What's being asked? Which finding would most directly support the team's conclusion about soil microbes explaining plant health differences.
What type of answer do we need? Evidence that would strengthen or validate their conclusion about certain microbes being responsible for the difference between healthy and diseased plants.
Any limiting keywords? Most directly support
Step 3: Prethink the Answer
- To support the conclusion that certain microbes explain plant health differences, we need evidence showing a clear difference in soil microbes between healthy and diseased plants, where these different microbes logically relate to disease resistance.
The soil surrounding healthy plants contained significantly higher concentrations of microbes known to inhibit Ralstonia solanacearum than the soil surrounding diseased plants did.
✓ Correct
- Shows healthy plants had higher concentrations of microbes that specifically inhibit the disease bacteria
- This directly supports the conclusion by demonstrating beneficial microbes correlate with plant health
The soil surrounding the plants contained high concentrations of Ralstonia solanacearum regardless of whether the plants were affected by wilt disease.
✗ Incorrect
- States that disease bacteria levels were high everywhere regardless of plant health
- This contradicts the microbe explanation by suggesting disease bacteria presence doesn't determine outcomes
The soil surrounding healthy plants tended to have significantly higher moisture levels than the soil surrounding diseased plants did.
✗ Incorrect
- Points to moisture levels as the distinguishing factor
- Doesn't mention microbes at all, so can't support a conclusion about microbes
By the end of the experiment, over half the plants had been affected by wilt disease regardless of differences in the types and concentrations of microbes in the surrounding soil.
✗ Incorrect
- States that plant disease occurred regardless of differences in microbes
- This directly contradicts the team's conclusion by saying microbe differences don't matter