What element has the symbol 'Bh'?

The story behind the answer

Bohrium is the element with the symbol Bh. It’s a synthetic, highly radioactive transactinide with atomic number 107, first produced in 1981 at GSI Darmstadt and named in honor of physicist Niels Bohr. The other options have different symbols: Bismuth is Bi, Berkelium is Bk, and Bromine is Br.

Memory tip: Bh = “BoHr-ium,” linking the letters to Bohr’s name. Bohrium sits in group 7 of the periodic table, beneath manganese, technetium, and rhenium, sharing similar chemistry, though only studied in trace, short-lived atoms. Its creation involved bombarding heavy targets with accelerated ions—an example of how superheavy elements are made and how modern nuclear physics extends the periodic table beyond naturally occurring elements.