Which trend contributes to the long-term impact of the us baby boom? a. rising immigration rates b. rising birth rates c. rising life expectancy d. rising retirement age

C. rising life expectancy is your answer.

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c. rising life expectancy 

In the baby boom, there were a large numbers of births after ww2, as many families were being established. Also, because of advancements in health-related fields, people were able to live longer. 

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