In the Nation of Pelmenia, 20% of 18-Year-Olds are Left-Handed, While Just 10% of 45-Year-Olds and 2% of 70-Year-Olds are Left-Handed.

Question: In the nation of Pelmenia, 20% of 18-year-olds are left-handed, while just 10% of 45-year-olds and 2% of 70-year-olds are left-handed. But the percentage of children born left-handed has never changed in Pelmenia, nor have societal attitudes toward left-handedness.

Which of the following, if true, most helps to explain the variation in left-handedness among Pelmenians?

A) The number of children born each year in Pelmenia has steadily increased over the past seventy years.
B) In Pelmenia, left-handers are no more likely to perish in accidents than right-handers.
C) In Pelmenia, ambidexterity is not considered a desirable attribute.
D) In Pelmenia, women have a significantly lower life expectancy than men, and women are also more likely to be born left-handed.
E) As Pelmenians age, they become less likely to participate in surveys regarding handedness or hand dominance.

“In the nation of Pelmenia, 20% of 18-year-olds are left-handed, while just 10% of 45-year-olds and 2% of 70-year-olds are left-handed.”-is a GMAT critical reasoning question. This GMAT Critical Reasoning topic has been taken from the book ‘GMAT Official Guide 2019’. GMAT critical reasoning tests the logical and analytical skills of the candidates. Critical reasoning in GMAT requires candidates to find the strengths and weaknesses of the argument, or find the logical flaw in the argument. The GMAT CR section contains 10 -13 GMAT critical reasoning questions out of 36 GMAT verbal questions.

Answer: D
Explanation: This is a GMAT critical reasoning question. We have to find the option. If true, it helps to explain the variation in left-handedness among Pelmenians.

Let’s go through each of the available options and select the most suitable one.

Option A: The number of children born each year in Pelmenia has steadily increased over the past seventy years.

This option is incorrect. In this question, we are explaining the variation in the percentage of Pelmanians who are left-handed. According to this option, the number of children born every year has increased. We would still expect the percentage of left-handed children to remain the same each year. This does not explain the variation. Option A is incorrect.

Option B: In Pelmenia, left-handers are no more likely to perish in accidents than right-handers.

This option is incorrect. We can explain the variation by the fact that left-handers are more likely to perish in accidents than right-handers. This could explain why the percentage of Pelmenians who are left-handed decreases as age increases. But this option states the opposite explanation. So, Option B is incorrect.

Option C: In Pelmenia, ambidexterity is not considered a desirable attribute.

This option is incorrect because just like option B, it states the opposite of the possible explanation. In case ambidexterity was considered a desirable attribute, it was possible for many left-handed Pelmenians. It would gradually learn to become ambidextrous over the course of their respective lives, which could lead to a decrease in the percentage of left-handed Pelmanians with age. Option C is incorrect.

Option D: In Pelmenia, women have a significantly lower life expectancy than men, and women are also more likely to be born left-handed.

This option is correct because according to this option, women are more likely to be born left-handed. We can safely assume that the majority of left-handed Pelmenian children are female. If women are dying at a younger age, we would expect the percentage of Pelmenians who are left-handed to fall as age increases. Option D is correct.

Option E: As Pelmenians age, they become less likely to participate in surveys regarding handedness or hand dominance.

This option is incorrect because it does not explain why the percentage of left-handed Pelmaniand decreases with age. It is eliminated because it does not explain the reasons for the variations. Option E is incorrect.

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