Answer:
B: a population’s age-sex structure
Step-by-step explanation:
A population pyramid is a way to visualize two variables: age and sex.
They are used by demographers, who study populations. A population pyramid is a graph that shows the distribution of ages across a population divided down the center between male and female members of the population. Expansive pyramids mean that the population does not increase much in total number and has many young people.
Hope this helps! Info from National Geographic, I would trust it if I were you!