The best answer is A.
The lytic cycle is considered the main cycle in viral replication. Once the viral DNA enters the cell, it transcribes itself into the host cell's messenger RNAs and uses them to direct the ribosomes.
The host cell's DNA is destroyed and the virus takes over the cell's metabolic activity and begins to use the cell's energy for its own propagation and within a short while, when the cell gets overcrowded with the viral progeny, the original virus releases enzymes to break the cell wall. The cell wall bursts. This process is called lysis. The new viruses are then released.
Microscopes allowed scientists to observe Prokaryotic cells which make up Bacteria and Archaea. These cells are small and contain no membrane- bound organelles. It allowed them to observe Eukaryotic cells with a nucleus and membrane-bound organelles that perform different life functions.
<span>epidemiological studies</span>
I believe the answer is A.