Final answer:
The Beta Clamp(d) is the correct answer for the component of the E. coli DNA Polymerase III monomeric unit, out of the options provided. It significantly increases the processivity of the DNA polymerase during bacterial DNA replication.
Step-by-step explanation:
The E. coli DNA polymerase III monomeric unit consists of multiple proteins; however, if we are to choose from the provided options, the correct answer is D) Beta Clamp. DNA polymerase III, in particular, is an oligomeric complex that is responsible for the majority of DNA synthesis during bacterial replication, and the Beta Clamp is an essential part of its ability to function efficiently by increasing the enzyme's processivity, which means that it can synthesize DNA for longer periods of time without dissociating from the template strand.
Other proteins that are associated with DNA polymerase III in E. coli but not listed in the options include the Tau and Gamma complex responsible for assembling the DNA polymerase onto the clamp and the helicase, as well as other subunits necessary for functionality. However, DNA polymerase I, Primase, and Helicase are separate and distinct enzymes participating in the replication process, but not components of DNA polymerase III itself.