Respuesta :
Selenium is a non metal, radon is a noble gas, silicon is a metalloid, and sulphur is a non metal. Hafnium is a transition metal.
Answer:
Hafnium
Explanation:
Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals