The correct answer is: Bromine.
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third member of the halogen group and is a highly reactive, corrosive, and flammable pale red-brown liquid at standard temperature and pressure. Bromine is the only non-metallic element that is liquid at standard conditions for temperature and pressure; the other four being metals.
Zinc is a chemical element with the symbol Zn and atomic number 30. It is a metal in the first transition series and is chemically similar to its two neighbors in the periodic table, copper and gallium. It is a moderately hard, silvery-white metal that oxidizes in air to form zinc oxide, and is used in many different applications.
Argon is a chemical element with the symbol Ar and atomic number 18. It is a member of the noble gases group in the periodic table and is a very unreactive element. Argon is the third most abundant gas in the Earth’s atmosphere, after nitrogen and oxygen.
Lead is a chemical element with the symbol Pb and atomic number 82. It is a heavy, dense, soft, bluish-white metal that is chemically similar to tin and antimony. Lead is used in many different applications, including batteries, ammunition, and solder.