Respuesta :
Answer: Option D) they require a microscope to be viewed.
Explanation:
Unlike bacteria, virus is a ultramicroscopic pathogenic particle capable of passing through bacteriological filters. So because, the virus is far much smaller than a bacterium, viewing a virus will always require a microscope (electron microscope to be precise) unlike a bacteria that is even visible in culture plates.
Thus, option D is the answer
Answer: d
Explanation:
Because bacteria is very small and cannot be seen by humans naked eye