The part of a microscope that passes light through the specimen is called the objective lens.

Here's a breakdown:

* Light source: This provides the illumination for the specimen.

* Condenser: It focuses the light from the source onto the specimen.

* Objective lens: This lens magnifies the image of the specimen. It is positioned close to the specimen, and its job is to gather light from the specimen and project it to the eyepiece.

The objective lens is crucial because it directly interacts with the specimen and determines the quality and magnification of the image.