All of the Following Have Been Causes of Major Transitions

All of the following have been causes of major transitions in Texas politics EXCEPT ______.

A) the immigration into the state of large numbers of Germans in the latter half of the nineteenth century
B) the Great Depression
C) the rise to prominence of cowboys in Texas government in the latter half of the nineteenth century
D) the increasing importance of oil in the Texas economy at the beginning of the twentieth century
E) the influx of Anglos into Texas in the early nineteenth century