[Solved] The bacterium that in part causes acne feeds on A) saliva. B) sudor. C) sebum. D) surface bacteria. E) more than one of these. Compound Light Microscope: An optical instrument that uses visible light and a system of lenses to magnify small objects or details not visible to the naked eye. 3-Dimensional: Describes an object or representation that includes depth, width, and height, providing a perception of volume and space. Working Distance: The distance between the objective lens of a microscope and the surface of the sample being observed. Objective Lens: A component of a microscope closest to the object being examined, focusing light or electrons to produce a magnified image.