Answer the Question. -A Researcher Looks at the Percentage of People Having High

Answer the question.
-A researcher looks at the percentage of people having high blood pressure amongst those who exercise regularly and amongst those who do not exercise regularly.
She selects 300 people under 40, of whom 200 exercise regularly and 100 do not. Among those who
Exercise regularly the rate of high blood pressure is 10% and among those who do not exercise
Regularly it is 15%.
She then selects 300 people over 40, of whom 100 exercise regularly and 200 do not. Among those
Who exercise regularly the rate of high blood pressure is 30% and among those who do not exercise
Regularly it is 35%.
However when she combines both age groups she finds that among those who exercise regularly
The rate of high blood pressure is 23.3% and among those who do not exercise regularly it is 21.6%.
Explain the apparent inconsistency in these results.

A) Among those who exercise regularly, younger people have a lower rate of high blood pressure, and among those who do not exercise regularly younger people have a lower rate of
High blood pressure. But looking at both groups combined, young people have a higher rate
Of high blood pressure.
B) In spite of exercising, people get older.
C) Within each age group the percentage with high blood pressure is lower amongst those who exercise, but when the age groups are combined, the percentage with high blood pressure is
Higher amongst those who exercise.
D) Within the under-40 age group the percentage with high blood pressure is lower amongst those who exercise, but within the over-40 age group, the percentage with high blood
Pressure is higher amongst those who exercise.