Why might we get a negative result when testing a food item when we know the molecules we're testing for are present?

i tried the eyeshadow trick you told me about and it worked so good i i did a yellow going into orange colors and it was bright and you could see it on my eyes

answer: a) a compound microscope has a greater magnification ability than a simple microscope.

explanation:

it is either c or d and i know for sure it is not a or b