Final answer:
The Class II pre-initiation complex consists of RNA polymerase II, general transcription factors, and promoter DNA, which together facilitate the transcription initiation process in eukaryotic cells.
Step-by-step explanation:
The Class II pre-initiation complex is an essential component in eukaryotic transcription and it comprises several elements. These include RNA polymerase II, which is responsible for synthesizing messenger RNA (mRNA) from a DNA template, as well as a range of general transcription factors (GTFs) that are required for the successful initiation of transcription.
General transcription factors are a set of proteins designated as TFII (standing for Transcription Factor/polymerase II) A through J that bind to specific sequences on DNA. Among these, TFIID, which includes the TATA-binding protein (TBP), recognizes and attaches to the promoter region of the DNA, setting up a scaffold for the assembly of the remaining transcription factors and RNA polymerase II. This carefully orchestrated process results in the formation of the transcription initiation complex, which also interacts with promoter DNA, a sequence where transcription begins.
As soon as RNA polymerase II is recruited to the promoter DNA by these factors, it, along with the general transcription factors, comprises the full pre-initiation complex. Consequently, the answer to what the Class II pre-initiation complex contains is 4) All of the above: RNA polymerase II, General transcription factors, and Promoter DNA.