15. Which one is incorrect?
(A)Bacteriophage T7 and related bacteriophage express a simple monomeric RNA polymerase. These polymerases recognize a 23-bp promoter region that includes the start site.
(B)Mitochondria contain circular DNAs transcribed by a nuclear-encoded RNA polymerase composed of two subunits. One subunit is homologous to the simple bacteriophage T7 RNA Polymerase; the other resembles bacterial σ factors.
(C)Chloroplasts contain DNA that is transcribed by a chloroplast-encoded RNA polymerase homologous to bacterial RNA polymerases, except that it lacks a σ factor.
(D)Archaeans utilize a multisubunit RNA polymerase that resembles the eukaryotic nuclear RNA polymerases. Transcription initiation in archaeal cells requires a protein, homologous to eukaryotic TBP, that binds to an G/C-rich promoter element just upstream from the start site and a protein homologous to TFIIB.