Which Statement About the Proteobacteria Is False

Multiple Choice

Which statement about the proteobacteria is false?

A) All groups of proteobacteria have retained the photoautotrophic nutritional mode.
B) The proteobacteria include some nitrogen-fixing genera.
C) Proteobacteria include many species of Gram-negative photoautotrophs that use light-driven reactions to metabolize sulfur.
D) Proteobacteria cause major human diseases, including cholera and bubonic plague.
E) The eukaryotic mitochondrion was derived from a proteobacterium.