Which of the following is not a part of compounds microscope?

A compound microscope typically consists of several parts including a mirror or light source (to illuminate the specimen), a stage (where the specimen is placed), clips (to hold the specimen slide in place), objective lenses (to magnify the specimen), an eyepiece or ocular lens (through which the observer views the specimen), and focusing knobs (to bring the specimen into sharp focus). The retina, however, is a part of the eye and not a component of the compound microscope.