Many organelles of the onion cells were not visible because ; ( D ) The remaining organelles can only be viewed with a scanning electron microscope
When cells are viewed under a light microscope most organelles of the cell cannot be seen clearly under a light microscope and even the organelles that are visible ( mitochondria, Nucleus ) are not very clear for scientific study due to the limitation in the resolution of the light microscope.
A scanning electron microscope scans the cell with a beam of electrons and produces a detailed image which shows the composition of the cell ( organelles )
Hence we can conclude that the remaining organelles can only be viewed with a scanning electron microscope.
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