clean the lenses with your fingers keep switching the magnifications carry the microscope with two hands at all times make sure to put the microscope on an uneven surface
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which safety measure should a student take when handling a microscope?
Possibilities:
- clean the lenses with your fingers
- keep switching the magnifications
- carry the microscope with two hands at all times
- make sure to put the microscope on an uneven surface

carry the microscope with two hands at all times