Which statement is incorrect with reference to inner transition elements?

Options

A. The oxides of lanthanoids are basic
B. Pm is radioactive element among actinoids
C. The values of ionisation enthalpy of actinoids are less than the values of ionisation enthalpy of lanthanoids
D. Only in the electronic configuration of lanthanoids like Ce, Gd, Lu the electrons are filled in 5d orbitals

Answer

B

Explanation

Pm is not actinoids.