Q. Which of the following elements is an actinide? Answer:
Curium
Notes: Curium (Cm) is a synthetic chemical element of the actinoid series of the periodic table, atomic number 96. This element of the actinide series was named after Marie and Pierre Curie – both were known for their research on radioactivity. Curium is a hard, dense, silvery metal with a relatively high melting point and boiling point for an actinide.