Question

even with the highest possible magnification of the light microscope, we can only see a blurry edge of the epithelial cells and cannot resolve the individual microvilli. why is it not possible to achieve a higher resolution in the light microscope? a). the speed of light is the limiting factor b) the wavelength of visible light is too long c) a higher resolution cannot be achieved because of the shape of the lenses d) the strength of light cannot be increased, otherwise the sample will heat up

Explanation:

The resolution of a light microscope is limited by the wavelength of the visible light it uses. The minimum distance two objects can be resolved is related to the wavelength of the illuminating light; longer wavelengths (like visible light, 400-700 nm) cannot resolve tiny structures smaller than approximately half their wavelength. Microvilli are far smaller than this threshold, so visible light's long wavelength prevents resolving them. Other options are incorrect: light speed does not limit resolution, lens shape affects magnification/resolution quality but is not the fundamental limit, and light intensity/heating is unrelated to the resolution limit.

Answer:

b) The wavelength of visible light is too long