Low levels of calcium in the blood are known to cause laryngeal polyps

Explanation to why option E is the correct answer:

Firstly, the study to predict the likelihood of patients developing polyps due to low calcium levels spanned for ten years.

The prediction of likelihood of patients developing polyps was made for two timelines - within first year and within five years.

Now, there would have been few patients who would have passed the 5 year mark while the study was still running and didn't develop polyps in reality but otherwise should have developed polyps as per the prediction made earlier -----> Overestimation of prediction, as the last line of the passage suggests.

We can conclusively say that the researchers would have come to know, before the study ended, of atleast few cases with overestimated predictions, since the study spanned for ten years and the five year mark fell within that timeline.

This one took a toll!

So basically, as someone rightly pointed out, this is an INFERENCE question - this understanding solves half of your question.
Trick to identify : Of the following claims, which is most strongly supported by the statements given?
Had they asked, which statement supports the claim made in the argument, it would have been a strengthen question.

Coming to the options :
A. At least some people observed during the study had an increase in blood calcium levels during the ten-year period.
NO : We do not know what caused the increase in the blood calcium levels. Never assume, unless specified.

B. People with the hereditary disorder are at no greater risk of developing laryngeal polyps than are people with low blood calcium levels who do not have the disorder.
NO : Once again, this has absolutely no relation to the argument being made.

C. The amount by which the researchers overestimated the likelihood of developing polyps decreased after the first five years of the study.
NO : It could be false if the researchers failed to learn from their mistakes and continued to make estimates that were flawed in the same way.

D. The percent of patients in the study with laryngeal polyps consistently increased over the ten-year period.
NO : The increase in the number of patients has got nothing to do with predicting the likelihood of all/some/none of them contracting the disease.

E. Prior to the end of the study, the researchers had reason to believe that at least some of their predictions had been overestimates.
YES: Makes sense, the argument clearly states "they almost universally overestimated the likelihood," which means some sort of a fact/error in prediction or a result made them believe about the over estimation.

MANHATTANPREP OFFICIAL EXPLANATION:

(A) The lower-than-expected incidence of LP isn’t necessarily due to an increase in BC. It could be due to a different medical factor, not discussed in the passage, or to a flaw in the researchers’ process.

(B) The passage includes no specific information about people without the hereditary disorder. The only information in the passage that applies to this population is the first sentence, which states that low BC causes LP. However, this does not provide any information about the relative likelihood of developing LP for people with or without the disorder.

(C) This answer choice could be false if the likelihood of developing LP changed significantly throughout the ten years. It could also be false if the researchers failed to learn from their mistakes and continued to make estimates that were flawed in the same way.

(D) The passage does not state whether LP can be cured; if they can, then the incidence of LP may actually have decreased during the study.

(E) CORRECT. The passage states that the study lasted ten years. The researchers overestimated the likelihood that participants would develop LP within five years. Also, the researchers were able to accurately determine whether participants had LP. Therefore, at the five-year point—prior to the end of the study—the researchers would have known that their initial five-year estimates were incorrect.

(A) At least some people observed during the study had an increase in blood calcium levels during the ten-year period.
=> incorrect. we know about the correlation between hereditary, low blood calccium, likelihood of polyps and likelihood of vocal paralysis but we don't know about the movement of low blood calcium in some patients

(B) People with the hereditary disorder are at no greater risk of developing laryngeal polyps than are people with low blood calcium levels who do not have the disorder.
=> incorrect the stimulus doesn't provide the comparison between people with the hereditary disorder and the people with low blood calcium who do not have the disorder

(C) The amount by which the researchers overestimated the likelihood of developing polyps decreased after the first five years of the study.
=> incorrect the stimulus doesn't provide this detail and we can't deduce it from stimulus

(D) The percent of patients in the study with laryngeal polyps consistently increased over the ten-year period.
=> incorrect the stimulus doesn't inform about the movement of the percent of patients with polyps

(E) Prior to the end of the study, the researchers had reason to believe that at least some of their predictions had been overestimates.
=> if ,over the 10 year study, the pattern that 1 year prediction is correct and 5 years prediction is always correct, the scientists would know about pattern in year 5 onwards. Hence, this statement E is correct

While reading every answer you have to say to yourself 3 things.

1. Can I prove it?
2. Not sure
3. Yeah. Maybe

(A) At least some people observed during the study had an increase in blood calcium levels during the ten-year period.
Study was conducted for 5 years, How do I know whether they had an increase in calcium levels in the next ten year period? - Can't Prove.

(B) People with the hereditary disorder are at no greater risk of developing laryngeal polyps than are people with low blood calcium levels who do not have the disorder.
People with the hereditary condition and without the condition have the same chances of developing polyps? - The Researchers didn't say or imply that- Can't prove

(C) The amount by which the researchers overestimated the likelihood of developing polyps decreased after the first five years of the study. - Come on bro, how do I know? - Still can't prove

(D) The percent of patients in the study with laryngeal polyps consistently increased over the ten-year period.
The study was conducted for 5 years only. I have no idea about what happened over the 10 year period - Sorry, Can't prove.

(E) Prior to the end of the study, the researchers had reason to believe that at least some of their predictions had been overestimates.
So yeah, for the next year's prediction maybe they were 99% accurate. As mentioned in the argument
For the second year maybe they were 50% and third year maybe 30%.
It might have come to their minds that maybe the 5 year prediction could be even less accurate. - Yeah Maybe its possible.

Hence E­

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