Answer: Option (d) is the correct answer.
Step-by-step explanation:
It is known that more is the electronegativity difference between the combining atoms, more polar is the bond formed by them.
Therefore, electronegativity difference for the given species is as follows.
Electronegativity of H = 2.2
Electronegativity of S = 2.58
Electronegativity of Cl = 3.16
Electronegativity of O = 3.44
Electronegativity of F = 3.98
Hence, electronegativity of H-S = 2.58 - 2.2 = 0.38
Electronegativity of H-Cl = 3.16 - 2.2 = 0.96
Electronegativity of H-O = 3.44 - 2.2 = 1.24
Electronegativity of H-F = 3.98 - 2.2 = 1.78
Thus, electronegativity difference is maximum for H-F.
Therefore, we can conclude that H-F is the most polar bond pair.