Which is the correct sequence in the following properties? For the correct order mark (T) and for the incorrect order mark (F):
(A) Lewis acidity order : SiF₄ < SiCl₄ < SiBr₄ < SiI₄
(B) Melting point : NH₃ > SbH₃ > AsH₃ > PH₃
(C) Boiling point : NH₃ > SbH₃ > AsH₃ > PH₃
(D) Dipole moment order : NH₃ > SbH₃ > AsH₃ > PH₃

(A) (F); As the size of halogen atom increases crowding on Si atom will increase, hence, tendency of attack of Lewis base decreases.
(B) (T); M.P. of NH₃ is highest due to intermolecular H-bonding in it.
Next lower M.P. will be of SbH₃ followed by AsH₃ due to high mol. wt. of SbH₃.
(C) (F);M.P. and B.P. of increase from PH₃ to SbH₃ via AsH₃ due to increase in mol.wt.NH₃ does not follow this trend due to intermolecular H-bonding.
Increasing B.P. order : PH₃ < AsH₃ < NH₃ < SbH₃
(D) (T); Value of bond moment decreases.