The answer is A. arm and base because it is the safest place to hold.
Holding
Everything on the light microscope is very expensive, so students should be careful when using any part of the light microscope. When carrying the light microscope, handlers must put one hand on the base at all times, to avoid dropping it, while the other hand should be on the arm. The microscope must never be carried upside down, since the ocular will fall out. It should never be swung when it is carried, according to Miami University.
