The Greater Prairie Chicken Once Flourished on the Prairies of Illinois.The

The greater prairie chicken once flourished on the prairies of Illinois.The conversion of prairie to farmland reduced their numbers from millions to only 50 birds by 1993.Poor genetic diversity resulted in only 50 percent of eggs hatching.Bringing in birds from neighboring states increased their genetic diversity,which improved the egg-hatching rate to 90 percent.These changes in genetic diversity were the result of:

A) loss of genetic diversity through natural selection and restoration of genetic diversity by genetic drift.
B) loss of genetic diversity through mutation and restoration of genetic diversity by gene flow.
C) loss of genetic diversity through genetic drift and restoration of genetic diversity by natural selection.
D) loss of genetic diversity through genetic drift and restoration of genetic diversity by gene flow.