Explanation:

- Oceans are teeming with viruses; they can survive and thrive in ocean waters, affecting marine life and even bacteria.

- Bacteria can be infected by viruses known as bacteriophages, which specifically target and attack bacterial cells.

- Many viruses can alter the cellular transcriptional activity of their host cells to replicate. This is a fundamental aspect of how they hijack host mechanisms.

- Correct Answer: Option 4, None

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