Step 1: Aromaticity Conditions.
For a compound to be aromatic, it must satisfy HΓΌckel's rule, which states that a molecule is aromatic if it has a planar ring structure with Ο-electrons (where is a non-negative integer).
Step 2: Analyze Each Compound.
- (A) This compound is not aromatic because it has 6 Ο-electrons (a common number for aromatic systems), but the ring is not planar, so it is not aromatic.
- (B) This compound has a nitrogen atom and a conjugated system, making it aromatic.
- (C) This compound contains a 6-membered ring with alternating single and double bonds, fitting the requirements for aromaticity with 6 Ο-electrons.
- (D) This compound has a conjugated system and satisfies the aromaticity condition with 6 Ο-electrons.
Step 3: Conclusion.
Thus, the aromatic compounds are (B), (C), and (D). The correct answer is (3).
Final Answer:
