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Video transcript

in this question were asked which one of the following if true would most help to explain the apparent discrepancy described above we can identify this question as an explained question the answer will provide information that makes the situation and the passage makes sense and the four wrong choices why they're not help the situation make sense or make the situation even more puzzling than it is pause your video now if you'd like to try this question on your own otherwise let's move on to the explanation okay let's read the stimulus together and as we do just focus on describing the discrepancy in your own words don't think about the answer yet the number of dear living in North America has increased dramatically since the 1960s even though hunters kill no fewer deer today moreover the number of natural predators of deer such as wolves is on the rise and suburbs increasingly encroach on deer habitats so with explained questions and resolved questions our first job is to describe the situation that doesn't seem to make sense we're told here that there are more deer living in North America since the 1960s great but we also learned that hunters kill no fewer deer today than they used to and we also learned that the number of deers natural predators is increasing and that suburbs are encroaching more and more on deer habitats we take all of the information together we would actually expect there to be fewer deer living today right so lots of threats to deer are flourishing and yet the number of deer has increased dramatically so let's freeze the discrepancy as a question why are there more deer today even though so many deer threats have increased we don't need to make a prediction for these question types because there could be so many possible explanations the most important piece is to understand the discrepancy in a very clear way now we move to the questions and evaluate each one against the discrepancy that we observed will ask does this choice as information provide the light bulb that we're looking for does it make us say okay now I understand why there are more deer living today even though so many deer threats have increased let's do it choice a pesticides that adversely affected most wildlife living in North America have been banned since the 1970s let's think about the impact of this information if pesticides that hurt most North American wildlife were banned since the 1970s that would explain why there are more deer they're no longer being hurt by the pesticides that means that a potentially major threat to deer has been removed even though other threats are on the rise it is reasonable that this threat is more important so on test day we could select this and move on to a new question let's look at the wrong choices in case you have questions about them be recently attempts have been made in various parts of North America to protect deer habitats from suburban development this doesn't help us first of all we don't know how recently these protective attempts have been made and we also don't know how effective those attempts were we don't know which parts of North America are counted when it says various parts meaning we don't know if those are significant parts so we've had to add way too many assumptions to justify this choice that's never a good thing when evaluating a choice untested a choice see the number of deer hunters in North America has decreased since the 1960s very first glance this could be tempting because it seems like a good thing for the deer if the number of deer hunters has decreased but remember what the passage told us hunters kill no fewer deer today so even though the number of hunters has gone down the hunters who are left are still killing as many deer if not more so the mystery remains d vaids much of the increase in the population of wolves is due to wolves born in captivity and released into the wild okay so this is explaining why there are more wolves but not at all why there are more deer we can rule this choice out since we know that our task is to explain that increase in deer finally II states the greater the number of deer the more likely they are to be afflicted with problems such as famine and disease this doesn't help explain why there are more deer today in fact if anything it makes the situation even more surprising since we're told that the number of deer has increased dramatically we would expect them to be more hurt by problems such as famine and disease so a choice that makes the situation even more surprising is the opposite of what we're looking for in an answer so to recap for explain questions you're reading with the purpose of formulating the discrepancy it's really helpful to form a question around it if you can why are there more deer today even though so many threats to deer have increased then pretend that each choice is a proposed answer to that question and pick the one that actually does answer the question and shed light on the situation