• When nitrobenzene reacts with LiAlH₄ in ether medium, it does not transform itself to amine, instead another product is formed which is azobenzene . So this reagent will not be a good choice for converting of nitrobenzene to amine.

Other 3 given reagents (i) H₂ (excess)/Pt (iii) Fe and HCl and (iv) Sn and HCl are actually efficient choice for the conversion.