Consider the following table$-$

Column-$I$	Column-$II$
$A$. Best and latest technique for isolation,purification and separation of organic compounds	$i$. Chromatography
$B$. In Lassaigne's test for $N$	$ii$. Vacuum distillation
$C$. In Lassaigne's test for $S$	$iii$. Violet coloured complex is formed
$D$. Aniline is separated from water by	$iv$. Prussian blue coloured complex is formed
$E$. Glycerol is purified from spent lye	$v$. Steam distillation

The correct match is$-$

Sodium fusion extract of aniline,when heated with ferrous sulphate solution and then acidified with concentrated $H_2SO_4$,forms which of the following complexes?

Three students,Manish,Ramesh,and Rajni were determining the extra elements present in an organic compound given by their teacher. They prepared the Lassaigne's extract $(L.E.)$ independently by the fusion of the compound with sodium metal. Then they added solid $FeSO_4$ and dilute sulphuric acid to a part of the Lassaigne's extract. Manish and Rajni obtained prussian blue colour,but Ramesh got red colour.
Ramesh repeated the test with the same Lassaigne's extract,but again got red colour only. They were surprised and went to their teacher and told him about their observation. Teacher asked them to think over the reason for this. Can you help them by giving the reason for this observation? Also,write the chemical equations to explain the formation of compounds of different colours.

For testing halogens in an organic compound with $AgNO_{3}$ solution,sodium extract (Lassaigne's test) is acidified with dilute $HNO_{3}$. What will happen if a student acidifies the extract with dilute $H_{2}SO_{4}$ in place of dilute $HNO_{3}$?

What happens when an organic compound is fused with sodium metal?

In the test for halogens,why is nitric acid added to the sodium fusion extract before adding silver nitrate?