The stimulus in this argument contains two conditional statements:
DG = dog growled WP = white poodle
Premise 1: DG → WP
Premise 2: WP → DG
Note that since this a Must Be True question, we must accept both of the above premises as true. Thus, we cannot claim that the second premise is a mistaken reversal of the first premise. This would only occur if we were attempting to infer the second premise just on the basis of the first premise. In this case Elena has stated both premises as facts and we thus accept them as true. This generates an interesting situation for Elena where every dog that growls at her is a white poodle, and every white poodle growls at her. Thus, each condition is both sufficient and necessary for the other condition. We can diagram such a statement as:
DG ↔ WP
The double-arrow indicates that both conditions must occur together, or that alternately neither of the two conditions will occur. There are no other possibilities in such a situation. Thus, answer choice (C) must be correct since if a dog growled at Elena, it had to be a white poodle. Answer choices (A) and (E) are both incorrect since they deal only with dogs that Elena saw at the show, not dogs that growled at her. Similarly, answer choice (B) is incorrect because it deals only with dogs at the dog show. Answer choice (D) is incorrect since it states that "All the white dogs that Elena saw growled at her," whereas her statements in the stimulus were specific to white poodles.
I just want to make sure I know why A and E are the wrong answers as well as B. Is it because they deal with only a part of the argument. For example if I have A<->B, than in this case, A, E and B are talking about one part A (seeing dogs a the show), and not the growling part which is B?
Thanks for your question. I would warn you against getting too formulaic in response to these--sometimes the right answer cannot be prephrased with certainty.
Answer choice (A) is incorrect because Elena may have seen other white dogs--her comments are limited to white poodles, so we don't know.
Answer choice (B) and (E) are wrong because Elena only discusses the white poodles she saw; there may have been grey ones, and she may have seen them. but she didn't mention it, so both answers fail the Fact Test, as they cannot be confirmed by the information in the stimulus.
I hope that helps--please let me know whether this is clear--thanks!
Hi! Although I got the right answer, I did not get the right answer by examining the conditional statement in answer choice C in relation to the conditional statements in the stimulus. Like the explanation above, I realized that "dog growled ↔ white poodle" from the stimulus, and thus the two must be together. So, no grey dogs could have growled at her (answer choice C).
However, when I focus purely on the formulas of the conditional statements, I don't see how I could come up with answer choice C. From Emily's explanation above, answer choice C is "grey dog dog growled." In other words: "a grey dog NOT dog growled" or the contrapositive "dog growled NOT grey dog." How does the conditional statement in answer choice C fit into the conditional statements in the stimulus (dog growled ↔ white poodle)? There is only one similar term between them ("dog growled"). Or, are we to equate "grey dog" = "NOT white poodle"?
Thanks for the question! Definitely fun to revisit a response I wrote 5 years ago - time flies when you're answering LSAT questions!
Your analysis is totally right, and I think probably the easiest way to solve this one. Don't worry at all about not being able to select the right answer based solely on diagramming the answer choices; your approach was great! But you are also right about how you can make it work using your diagrams; a grey dog is, by definition, NOT a white poodle.
Thanks for the question! This is a common misconception - that if there is new information in the answer choices, it has to be wrong. But as we can see here, that's not necessarily true (I'd venture to guess, in fact, that the LSAT testmakers were counting on people to see the word grey here and rule it out automatically). The key is to think logically about the answer choices, and if they are proved by the stimulus. Elena states that "While I was at the dog show, every dog that growled at me was a white poodle" - so we can conclude that no other types of dogs growled at her. This proves answer choice (c): "At the dog show, no gray dogs growled at Elena." We can think of a grey dog as a non-white dog, which we know could not have growled at Elena. Hope this helps!