In which of the following sets the order of boiling points are incorrect?

The correct order of boiling point of hydrogen halides is HBr > HCl > HF because as the molar mass of halogen increases the boiling point increases. Hence, option C is correct. The order given in option C (HF > HCl > HBr) is incorrect. The higher boiling point of HF is due to strong hydrogen bonding. However, this effect is not strong enough to overcome the effect of increasing molar mass in the other hydrogen halides.