LR Question 26 Explanation
QUESTION TEXT: Farmer: Crops genetically engineered to produce…
QUESTION TYPE: Necessary Assumption
CONCLUSION: Using genetically modified (GMO) crops will help wildlife.
REASONING: GMO crops don’t need pesticides, and pesticides sprayed on crops hurt wildlife.
ANALYSIS: The author is assuming that the GMO crops won’t harm wildlife, or will harm them less than pesticides do.
___________
- CORRECT. If this isn’t true, then GMO crops will not be better than pesticides.
Negation: GMO crops will cause at least as much harm as pesticides. - This is a silly statement. “Even slightly” could mean one micro-gram less pesticides. This sort of answer could never impact anything.
- It doesn’t matter if GMO crops are never sprayed with pesticides. It only matters whether they are sprayed less often.
Negation: GMO crops are sprayed with pesticides, but only 0.000000001% as much as regular crops. - It doesn’t matter how much crops cost. Cost would affect whether GMO crops are used, but the stimulus is only about what happens if they are used. That’s a different question.
- Ugh, what a complex answer.
We’re trying to prove that GMO crops will help. This answer adds a necessary condition for GMO crops helping. That’s no good. Adding an extra necessary condition makes it harder to do something.
I get why A is right, but am confused about why B is wrong. If the animals aren’t likely to recover if less pesticides are sprayed, doesn’t that also cause the conclusion to fall apart?
The confusion might stem from a wrong negation of B. The negation of B is more like: A slight reduction in insecticide use is not enough to make harmed wildlife populations likely to recover.
If this were true, the farmer’s argument could still be fine. Maybe a small reduction isn’t enough, but using these crops could lead to a large reduction, and then wildlife could recover. So B is adding this extra idea that even tiny reductions are enough for recovery, but the argument never depended on that.
What the farmer is actually trying to prove is that using the genetically engineered crops will make wildlife recover. So we need something that tells us that switching methods will reduce harm compared to what we’re doing now (spraying), which is what A gives us.
Hope that helps! Let me know if you have further questions.
OK that makes sense, thank you! So would you say B is sufficient, but A is necessary?
B isn’t sufficient, no. For something to be sufficient it means it guarantees the conclusion. B only says that wildlife harmed by insecticides are likely to recover if spraying is reduced slightly. But it doesn’t establish that wider use of genetically engineered crops will reduce overall harm to wildlife, since those crops could harm wildlife in other ways. So B could be true while the farmer’s conclusion is false, so it’s not sufficient.
This one confuses me. On prediction, I really honed in on the fact that it says the genetically altered crops will help wildlife RECOVER. So the assumption I was looking for was that planting altered crops will reduce spraying, and if spraying is reduced, wildlife will recover. How does less harm equate recovery? Thanks!
It’s not that less harm will equate in recovery, it’s that recovery is impossible unless it does less harm, because currently there is a sort of “threshold” level of harm being done to the wildlife populations because of the spraying. If we replace spraying with GMO crops, but the crops are still hurting wildlife somehow (irrelevant how or why) then it’s impossible for wilder use of GMO crops to help wildlife populations recover.