You are presented with the question "Viruses are so small that to see them a scientist would have to use what kind of lens?" and the following answer choices: 
- Refract it
 - refraction of light
 - an electron lens
 - an image
 - rays or beams
 - bending light rays
 - A computer
 - flashlights

Now knowing that viruses are so small that they can be seen only with an electron microscope and on the surface of each microscopic color filter is also a microscopic lens, choose the best answer.


 

   an electron lens      