After Binding by E

After binding by E.coli RNA polymerase,the correct order of events for transcription initiation is:

A) closed complex formation,open complex formation,promoter clearance,start of RNA synthesis.
B) closed complex formation,open complex formation,start of RNA synthesis,promoter clearance.
C) open complex formation,closed complex formation,start of RNA synthesis,promoter clearance.
D) start of RNA synthesis,closed complex formation,open complex formation,promoter clearance.
E) start of RNA synthesis,open complex formation,closed complex formation,promoter clearance.