Select from the following. (a). blood (b). flight (c). damage (d). disease
Given those answer options, answer the question: Answer the following question given this paragraph: Viruses are so small that they can be seen only with an electron microscope. Before electron microscopes were invented, scientists knew viruses must exist. How did they know? They had demonstrated that particles smaller than bacteria cause disease. Q: They had demonstrated that particles smaller than bacteria cause what? A:
A:
(d).