Final answer:
The PhiX174 primosome consists of primase and helicase. While DNA Polymerase I and III partake in the DNA replication process, only primase synthesizes the RNA primer, and helicase unwinds the DNA, marking them as part of the primosome.
Step-by-step explanation:
The proteins that are ALL components of the PhiX174 primosome include primase and helicase. Primase (D) is an enzyme that synthesizes a short RNA primer to be used as a starting point for DNA synthesis.
Helicase (A) is an enzyme that unwinds the DNA helix at the replication fork, allowing the DNA to be copied. While DNA Polymerase I and DNA Polymerase III are involved in DNA replication, they are not considered components of the primosome in the context of PhiX174 replication. Instead, DNA Polymerase I (C) is involved in the removal of RNA primers from the lagging strand and their replacement with DNA, and DNA Polymerase III (D) is the primary enzyme responsible for DNA synthesis during replication.