Explanation
B: Osmium is considered the heaviest metal in the world, with a density of 22.59 g/cm³. Osmium is a chemical element with the symbol Os and atomic number 76. It is a hard, brittle, blue-gray or blue-black transition metal in the platinum group. Osmium has a high melting point and is one of the densest elements on Earth. It is primarily used in alloys with other metals, such as platinum, to increase their hardness and durability. The density of osmium is more than twice that of lead, which is often considered the heaviest stable element. Therefore, osmium is the heaviest known element at room temperature and pressure.
