Step 1: Understanding aromatic compounds.
Aromatic compounds are those which contain a planar ring system with delocalized \(\pi\)-electrons and follow Huckel’s rule \((4n+2)\pi\) electrons. Such structures provide extra stability and are commonly seen in benzene-like rings.
Step 2: Structural analysis of vitamins.
Vitamin K contains a naphthoquinone ring, which is an aromatic system.
This aromatic ring is responsible for the chemical stability and reactivity of Vitamin K.
Step 3: Analysis of options.
(A) Vitamin A: It is a long-chain polyene and does not contain an aromatic ring.
(B) Vitamin C: It is an aliphatic compound with no aromatic ring.
(C) Vitamin B complex: These vitamins have diverse structures, mostly heterocyclic but not aromatic in nature.
(D) Vitamin K: Correct — it contains an aromatic naphthalene-based structure.
Step 4: Conclusion.
Vitamin K is the only vitamin among the given options that belongs to the aromatic series.