Final answer:
The correct answer is D) All of the choices are correct because once inside the host cell, phage DNA can be replicated, transcribed, and could also be degraded by bacterial nucleases depending on whether the lytic or lysogenic cycle is initiated.
Step-by-step explanation:
Once inside the host cell, phage DNA undergoes various processes that may include replication, transcription, and potential degradation by bacterial nucleases. Thus, the correct answer to the student's question is D) All of the choices are correct.
In the lytic cycle, the phage DNA is replicated and transcribed to synthesize new viral components, ultimately leading to the destruction of the host cell to release the new phage particles into the environment. In contrast, during the lysogenic cycle, the phage DNA is incorporated into the host genome and may stay dormant until an environmental stressor triggers the lytic cycle. Additionally, entry of the phage DNA into the bacterial cell can activate bacterial nucleases that may degrade the viral DNA if it's not protected or integrated quickly enough.