GMAT Critical Reasoning (CR) | Re: A birth is more like to be difficult when the mother is over

A birth is more like to be difficult when the mother is over the age of 40 than when she is younger. Regardless of the mother’s age, a person whose birth was difficult is more likely to be ambidextrous than is a person whose birth was not difficult. Since other causes of ambidexterity are not related to the mother’s age, there must be more ambidextrous people who were born to women over 40 than there are ambidextrous people who were born to younger women.
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