The correct order of increasing intermolecular hydrogen bond strength is

The strength of Inter molecular Hydrogen bond decreases in the following order

Order of H-Bonding: CH₄ < HCN < NH₃

For stronger hydrogen bond the size of electronegative atoms should be small. The smaller the size of electronegative atoms, the greater is the attraction for the bonded electron pair. This causes greater polarity in the H and the electronegative atom, resulting in stronger intermolecular hydrogen bonding.

NCH . . . NCH

H₂NH . . . NH₃

Methane doesn't form hydrogen bonds and H₂O much stronger hydrogen bonds than NH₃.