Magnifying power of simple microscope is inversely proportional to the focal length of the lens . What then stops us from using a convex lens of smaller focal length and achieve greater and greater magnifying power ?

Question

$\begin{array}{1 1} \text{chromatic and spherical aberration are more pronounced } \\ \text{chromatic and spherical aberration are less pronounced } \\ \text{It is difficult to make lesser of very small focal length } \\ \text{none of these} \end{array} $