$A$ country with a high rate of population growth took measures to reduce it. The figure below shows age-sex pyramids of populations $A$ and $B$ twenty years apart. Select the correct interpretation about them.

• A
  $B$ is the earlier pyramid and shows a stabilized growth rate.
• B
  $B$ is more recent,showing that the population is very young.
• C
  $A$ is the earlier pyramid and no change has occurred in the growth rate.
• D
  $A$ is more recent and shows a slight reduction in the growth rate.