The correct order of dipole moments for the given species is

Step-by-step solution

The dipole moment of a molecule depends on its geometry and the vector sum of its individual bond dipoles. BF ₃ has a symmetrical trigonal planar geometry. The three B-F bond dipoles cancel each other out completely, resulting in a net dipole moment of zero ( = 0 ). NH ₄^+ has a symmetrical tetrahedral geometry. The four N-H bond dipoles cancel each other out, resulting in a net dipole moment of zero ( = 0 ). Thus, ( BF ₃) = ( NH ₄^+) = 0 . Both NH ₃ and NF ₃ have a trigonal pyramidal geometry with one lone pair on