1. Analyze $NH_3$ (Ammonia): The central nitrogen atom has 5 valence electrons. It forms 3 sigma bonds with Hydrogen atoms and has 1 lone pair ($5-3=2$ electrons $\rightarrow$ 1 pair). The arrangement of 4 electron pairs is tetrahedral, but the presence of one lone pair distorts the shape to Trigonal Pyramidal . (Match: A-I)
2. Analyze $BrF_5$ (Bromine Pentafluoride): Bromine (Group 17) has 7 valence electrons. It forms 5 single bonds with Fluorine. Remaining valence electrons = $7-5=2$ (1 lone pair). With 5 bond pairs and 1 lone pair, the geometry is octahedral, and the shape is Square Pyramidal . (Match: B-IV)
3. Analyze $XeF_4$ (Xenon Tetrafluoride): Xenon (Group 18) has 8 valence electrons. It forms 4 single bonds with Fluorine. Remaining valence electrons = $8-4=4$ (2 lone pairs). With 4 bond pairs and 2 lone pairs, the geometry is octahedral, and the shape is Square Planar to minimize repulsion . (Match: C-II)
4. Analyze $SF_6$ (Sulphur Hexafluoride): Sulphur (Group 16) has 6 valence electrons. It forms 6 single bonds with Fluorine. Remaining valence electrons = 0. With 6 bond pairs and 0 lone pairs, the shape is regular Octahedral . (Match: D-III)

Conclusion: The correct matching code is A-I, B-IV, C-II, D-III.