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PrepTest 73, Game 4, Question 23


And now question 23 is the last question. It's a global question that wants to know about what must be false, or what can't be true. There's nothing in the question stemmed to help us, we're just gonna have to use a combination of our previous work and any testing we might need to do, to eliminate answer choices to get down to one answer.

So answer choice A says that L and R are the only kinds of flowers in bouquet one. We've actually seen that before. That was part of the correct answer to question 19. So since we've seen it before, we know that it could be true. So it's not something that must be false. Answer choice B says that P and T are the only kinds of flowers in bouquet one, which we have also seen before in question 21, bouquet 1 has T and P.

Answer choice C says that L, P and R are the only kinds of flowers in bouquet two. Now this one, we have actually never seen before. So maybe this is something that can't happen, but we don't know, all we know is it hasn't happened so far. So then we'll go to answer choice D. And D says that PRS are the only flowers and bouquet 2, which that could happen because remember, we can add an extra P to the sketch for question 21, you could have PRS in bouquet 2.

And then answer choice E, P, S and T are the only types of flowers and bouquet three. We actually have seen that in question 19 as well. So because we've seen A, B, D and E, we know that C must be the answer. If the others can be true, then C must be the one that can't be true. Of course, we might wanna know why it is that C can't be true, just independently.

And it takes a little bit of extra thinking to get there, but basically if bouquet two were to have only P, R and L. It would have to share the P and R with bouquet three, because bouquet three could never have an L and bouquet two and three have to have two in common. But then that means bouquet one won't be allowed to have P, R, or S, because those would be in bouquet three.

And if we get rid of P, R and S, we also to get rid of T and L, because there are rules that say if you don't have T, you can't have P and if you don't have R, you can't have L. So basically, bouquet one would have nothing that it could have, if bouquet two were to have answer choice C's selection of flowers. So answer choice C it is our answer and with that, we are done with the game.

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