What is the purpose of age structures?

a. they provide a way to study the overall age demographics of a population.
b. they can be used to plan for the number of nursing homes needed in a given area.
c. to advocate for small class sizes in schools
d. to know how many children live in a specific community

A. They provide a way to study the overall age demographics of a population.

Explanation:

" it's a summary of the number of individuals of each age in the population. Age structure is useful in understanding and predicting population growth."

the fossil record provides evidence of a common ancestor to many species.

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.