PrepTest 109, Section 4, Question 14
When soil is plowed in the spring, pigweed(69 more words not shown)
The statements above, if true,(32 more words not shown)
- AFewer pigweed plants(20 more words not shown)
- BFewer pigweed plants(20 more words not shown)
- CFewer pigweed plants(20 more words not shown)
- DThe pigweed seeds(26 more words not shown)
- EAll of the(18 more words not shown)
Reading the argument
The plow isn't simply bringing the seeds closer to the surface. It briefly brings them into sunlight, and that exposure sets off a process inside the seeds.
The winter underground matters too. Those months of darkness make the receptors highly sensitive. The passage gives us a sequence: prolonged darkness, then sunlight, then the stimulated receptors trigger germination. We don't have an argument to attack here; we have a process to understand.
What we’re looking for
The question describes a field where the seeds have been buried all winter and asks what is most supported when it is plowed in spring. I'd expect the described sunlight exposure to trigger germination. I wouldn't jump from that to “Every seed will become a plant” or “The whole field will be covered in weeds.” We should look for an answer that follows the process without adding more than we know.
Working the answers
- ACorrect
Plowing at night changes the sunlight part of the sequence. The seeds have already spent the winter in darkness, but when they are churned up at night, they don't receive the brief exposure to sunlight that daytime plowing provides. They are then redeposited under the surface.
That gives us a reason to expect fewer plants with nighttime plowing. The important darkness is the long period of winter burial; nighttime plowing doesn't create a better version of that requirement. It avoids the burst of sunlight that would stimulate the seeds. A uses the timing of the plowing to interrupt the described trigger.
- B
We aren't given a reason that leaving the field unplowed produces fewer plants than plowing it at night. Neither option supplies the daytime exposure described in the passage. We also aren't told everything that might bring a buried seed into sunlight without a plow. The information doesn't establish the comparison B makes.
- C
Just before sunrise and just after sunset are both times without the daytime sunlight exposure. The seeds have already had prolonged darkness over the winter, so we don't need to give them a longer stretch of night to satisfy that part of the process. Nothing here supports C's claim that one of these nighttime choices will produce fewer plants than the other.
- D
The passage says the seeds are redeposited under the surface. It doesn't say that reburial is required for germination. The explicitly required sequence is prolonged darkness followed by sunlight. D takes something that happens during the described plowing process and turns it into an additional requirement.
- E
These seeds were already on the surface. We don't know that they experienced the prolonged darkness needed before sunlight can trigger germination. The passage describes what happens to seeds buried all winter, not every seed already lying on top. E's claim about all of them goes beyond that information.
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