The correct statements among the following are,
A. Mo(VI) and W(VI) are less stable than Cr(VI).
B. CeX4+ and TbX4+ are oxidant while EuX2+ and YbX2+ are reductant.
C. Cm and Am have seven unpaired electrons.
D. Actinoid contraction is greater from element to element than lanthanoid contraction.
Choose the correct answer from the options given below: