Option 1 -> Incorrectly matches Neurologist with heart diseases instead of nerve-related diseases.
Option 2 -> Correctly matches: Neurologist with nerve diseases (IV), Orthodontist with teeth straightening (III), Cardiologist with heart diseases (I), and Pathologist with disease diagnosis (II).
Option 3 -> Incorrectly matches Neurologist with disease diagnosis and Pathologist with teeth straightening.
Option 4 -> Incorrectly matches Neurologist with teeth straightening and mixes up other specializations.
Hence, Option 2: (A) - (IV), (B) - (III), (C) - (I), (D) - (II) -> Each medical specialist is correctly paired with their field: Neurologist treats the nervous system, Orthodontist corrects teeth alignment, Cardiologist treats heart conditions, and Pathologist studies disease causes through diagnosis and laboratory analysis -> correct