Which of the following statements is not correct?
(A) The first ionization energies (in KJ ) of carbon, silicon, germanium, tin, and lead are 1086, 786, 761, 708 and 715 respectively.
(B) Down the group, electronegativity decreases from B to Tl in boron family.
(C) Among oxides of the elements of carbon family, CO is neutral, GeO is acidic and SnO is amphoteric.
(D) The 4f- and 5f- inner transition elements are placed separately at the bottom of the periodic table to maintain its structure.