What does the RNA polymerase holoenzyme consists of in
prokaryotes? Select one: a. the core polymerase plus two alpha
subunits. b. the core polymerase plus two alpha subunits, two beta
subunits, and a sigma subunit. c. the core polymerase plus a sigma
subunit. d. the core polymerase plus two beta subunits. e. two
alpha subunits, two beta subunits, and two sigma subunits.