Stage I DNA replication in the bacteriophage ϕX174 is carried out entirely by host cell proteins.Why?

A) DNA replication is required for penetration of the viral genome into the host cell.
B) The bacteriophage ϕX174 does not encode any of its own DNA replication proteins.
C) The phage genome has become integrated into the host genome.
D) Only the host cell proteins can replicate a ssDNA genome.
E) Stage I DNA replication occurs before any viral proteins are expressed.