Correct answer:

A sebaceous cyst (epidermoid cyst or wen) is a retention cyst produced by obstruction to the mouth of a sebaceous gland. Therefore sebaceous cysts may occur wherever sebaceous glands exist and are not found on the gland-free palms and soles. They are especially common on the scalp, face, scrotum and vulva and on the lobe of the ear. The cyst is fluctuant and cannot be moved separately from the overlying skin. There may be a typical central punctum and the contents are cheesy with an unpleasant smell. The lining membrane consists of squamous epithelium.