LSAT 158 | Section 4 | Logical Reasoning: Q24

LR Question 24 Explanation

QUESTION TEXT: Consumer advocate: Some agricultural crops are now…

QUESTION TYPE: Weaken

CONCLUSION: The drugs will end up in the general food supply.

REASONING: Pollen from a drug crop and non-drug crop of the same species can interbreed, and turn the latter also into a drug-producing crop.

ANALYSIS: There’s a difference between a plant and the general food supply. For example, let’s consider a stalk of corn. Do we eat every part of the cornstalk? No! We just eat the kernels, not the ear, the husk, or the rest of the plant. So if the drug is only in the parts of the plant that we don’t eat, then it probably won’t get into the general food supply.

Note that the conclusion is very specific. The only claim is that some amount of drugs will get into the food supply. It doesn’t have to be a ton, and we don’t have to know how. The argument only requires that it does happen.

___________

1. The argument wasn’t about whether the drugs are harmful, but whether or not they will be present in the food supply.
2. This answer choice is an incorrect negation of the premises. This type of answer may use familiar words, but incorrectly negating a premise from the stimulus will basically never be the basis of right answer. Look for logical structure, not familiarity.
3. The drug doesn’t need to comprise the largest portion of the general food supply. The argument was only about whether the drug would enter the food supply. (in any amount)
4. CORRECT. Exactly. The drugs aren’t present in parts of the plant used for food, so it wouldn’t end up in the general food supply.
5. We don’t care if we can later identify the crops. We only care if the drugs enter the food supply. Drugs can do so whether or not we identify the crop.
    
   This answer may be implying that if scientists can identify crops then they can stop the drugs. But maybe it takes five hours and $500 to identify a drugged plant: it would be too expensive to do that at scale if drugged plants became widespread. There are billions of plants on farms!

Recap: The question begins with “Consumer advocate: Some agricultural crops are now”. It is a Weaken question. Learn more about LSAT Weaken questions in our guide to LSAT Logical Reasoning question types.