7 DDT is a pesticide that was once widely used to control agricultural pests and mosquitoes. However, this pesticide caused the eggshells of certain birds, including the
brown pelican, to become fragile and thin. The adults would then accidentally crush the
eggs while trying to incubate them.
What happened to brown pecan populations as a result of DDT use by humans?
A The populations increased much more slowly.
B The populations decreased as fewer eggs survived long enough to hatch.
C The populations remained stable over time.
D The populations increased as pelicans laid more eggs so that more offspring would
survive.