Answer:
Option b. A long focal length objective and a short focal length eyepiece
Explanation:
A microscope is an optical instrument which is used to get magnified images of the objects that can not be seen with naked eyes.
Therefore, a good microscope is characterized by the degree of magnification it provides and the magnification of a lens is given by the relation:
[tex]magnification, m = \frac{objective lens' focal length}{eyepiece lens' focal length}[/tex]
From the above relation it is clear that higher degree of magnification can only be achieved by having greater focal length of objective lens and smaller focal length of eyepiece.
