Why Must the Microviruses Produce DsDNA Before Viral Genes Can

Why must the microviruses produce dsDNA before viral genes can be expressed?

A) Only dsDNA can be packaged into virions.
B) DsDNA is more stable than ssDNA.
C) Only dsDNA is a substrate for transcription by the host RNA polymerase.
D) Only dsDNA is a substrate for replication by the host DNA polymerase.
E) The viral regulatory proteins can only bind to double-stranded DNA.