LIST - 1                   LIST - 2
A) Benzene          1) Heterocyclic
B) Pyridine           2) Alicyclic
C) Cycloalkane    3) Aliphatic
D) Alkane             4) Aromatic
                               5) unsaturated aliphatic

Aromatic compounds are the compounds which have ring structure, shows unsaturation, planar and follow Huckel's rule.

•  Benzene is an aromatic compound as it follows all these criteria of aromatic compounds
• Pyridine is a heterocyclic compound as it contains nitrogen in the ring structure in the place of one of the carbon atom. Heterocyclic compounds are the compounds which have one element different than that of the carbon atom in the ring structure.
• Alkane is an aliphatic compound as it has an open chain structure.
• Cycloalkane does not contain alternate single or double bond and hence it is an alicyclic compound.

Hence, the correct answer is option (A) 4 1 2 3.