BF3 has trigonal planar geometry. B has 3 bond-pairs and 0 lone pair of electrons. ClF3 has T-shape geometry. Cl has 3 bond pairs and 2 lone-pairs of electrons. Electronic geometry will be trigonal bipyramidal. NH3 has trigonal pyramidal geometry. N has 3 bond pairs and 1 lone-pair of electrons. NH4+ has tetrahedral geometry. N has 4 bond pairs. Hence, correct match is A→II,B→III,C→IV,D→I