वैज्ञानिक और अर्थ संबंधी वर्गीकरण के आधार पर उस शब्द की पहचान कीजिए जो समूह से संबंधित नहीं है।

Choose the pair that is different from the other pairs based on a specific logic.

Based on alphabetical order, three of the following four letter-clusters are alike in a certain way and thus form a group. Which is the one that does not belong to that group? (Note: The odd man out is not based on the number of consonants/vowels or their position in the letter cluster)