Answer:The upper part of the microscope that contains the eyepiece tube and prisms

Explanation:Ocular Lens (Eye Piece)2. Diopter Adjustment3. Head4. Nose Piece5. Objective Lens6. Arm (Carrying Handle)7. Mechanical Stage8. Stage Clip9. Aperture10. Diaphragm11. Condenser12. Coarse Adjustment13. Fine Adjustment14. Illuminator (Light Source)15. Stage Controls16. Base17. Brightness Adjustment18. Light Switch