RC Question 22 Explanation
DISCUSSION: This is covered on lines 35-44. It’s a bit confusing.
The land in the experiment was recently cultivated. Some nearby land had been out of production for 20 years.
Researchers took soil from the land that had been out of production, and they spread the soil on the recently cultivated land.
Plants grew better on the recently cultivated land when researchers scattered the soil. This was because the soil had helpful microorganisms. (lines 38-41).
However, plants still grew better on the land that had been out of production (lines 43-44). That is, the land that had been out of production for 20 years.
The reason? The recently cultivated, farmed land was overrun with harmful microorganisms, and lacking helpful microorganisms (lines 44-50).
___________
- This fact is out of context, it comes from lines 5-8. Lines 44-50 make clear that the problem with these particular plots of land was that they were overrun with harmful microorganisms.
- CORRECT. See lines 44-50.
- This is a fact from lines 8-12, it’s out of context here.
- It’s worse than this. Farmed land not only lacks helpful microorganisms, it’s also overrun with harmful ones (lines 44–50). But D also misattributes this to natural soil, which isn’t the problem. The harmful microorganisms are found in the recently farmed land, not the natural soil.
- This is backwards. The farmed land had harmful microorganisms (lines 44-50).
The land that was out of production had helpful microorganisms (lines 38-41).
I quite didn’t understand what you mean by “it’s worse than this” for the explanation of answer choice D.
As you said “Not only does farmed land lack helpful microorganisms: farmed land is full of harmful microorganisms (lines 44-50),” I wonder how I can choose answer choice B over D since both are supported by the above lines.
Thank you!
Good question. You have to read the whole paragraph. Basically farmers have two plots under discussion here:
1. Natural soil, out of production for 20 years
2. Recently farmed land, but where some natural soil is also added
The first one did better than the second. The lines you’re citing are talking about the problems with recently farmed land. This recently farmed land is both lacking good organisms and overrun with bad organisms.
B is correct because it states half of this: there are bad microorganisms.
D, by contrast, is referring to the wrong thing. It refers to natural soil. Natural soil isn’t the problem. So D incorrectly takes something true about farmed land and says it’s true of natural soil instead.
Going to update the explanation to be clearer, thanks!