The correct answer is option 3: Mercury. Cinnabar is an ore that primarily consists of mercury sulfide (HgS). Ores are naturally occurring minerals that contain a valuable metal or element. In the case of cinnabar, it is a source of mercury. Mercury is a heavy, silvery metal that is liquid at room temperature and has various applications in industries such as thermometers, electrical switches, and fluorescent lights. It is also used in the production of chlorine and caustic soda.

Options 1, 2, and 4 are incorrect. Copper is typically found in ores such as chalcopyrite and malachite. Zinc is commonly found in ores like sphalerite and smithsonite. Manganese is primarily found in ores such as pyrolusite and rhodochrosite. None of these ores are associated with cinnabar. Therefore, the correct answer is option 3: Mercury.

It is important to note that mercury is a toxic substance and proper precautions should be taken when handling it.