The correct answer is option 2: Au (gold). Gold is a metal that exhibits both malleability and ductility properties.

Malleability refers to a material`s ability to be deformed under compression, such as being hammered or rolled into thin sheets without breaking. Gold is highly malleable, and it can be easily molded and shaped into various forms, including thin foils.

Ductility, on the other hand, refers to a material`s ability to be stretched into a wire without breaking. Gold is also highly ductile and can be drawn into fine wires that are thinner than a human hair.

Option 1: Na (sodium) is a metal that is malleable but not as ductile as gold.

Option 3: Ce (cerium) is a rare earth metal that is relatively brittle and not as malleable or ductile as gold.

Option 4: Hg (mercury) is not a good example of a metal with malleability and ductility. Mercury is a liquid at room temperature and does not exhibit these properties.

Therefore, the correct answer is option 2: Au (gold), as it is both malleable and ductile.