(1) It has an unpleasant odour like rotten fish
(2) It precipitates out of metals from their aqueous salt solutions as metallic phosphates
(3) It burns in air or oxygen giving phosphorus trixoide and water
(4) It cannot be prepared by heating phosphorus acid
(5) Phosphine is an ionic molecule
$\begin{array}{1 1} (3), (4) and (5) are all incorrect \\Both (3) and (5) are incorrect \\ Both (4) and (5) are incorrect \\ Both (3) and (4) are incorrect \end{array}$
