Answer:
Option B
Explanation:
Magnification of Microscope is
[tex]M = M_o \times M_e[/tex]
Mo= Magnification of objective lens and
Me= magnification of the eyepiece.
Both magnifications( of objective and eyepiece) are inversely proportional to the focal length.
Magnification,
[tex]M \propto \dfrac{1}{f}[/tex]
when the focal length is less magnification will be high and when the magnification is the low focal length of the microscope will be more.
Thus. Magnification will increase by decreasing the focal length.
The correct answer is Option B
