The actinoids exhibit more number of oxidation states in general than the lanthanoids. This is because
A. the 5f orbitals are more buried than the 4f orbitals
B. there is a similarity between 4f and 5f orbitals in their angular part of the wave function
C. actions are more reactive than lanthanoids
D. the 5 f orbitals extend farther from the nucleus than the 4 f orbitals
