Answer : The correct answer is C) Hydrogen bonds .
Melting of ice means conversion of solid phase of ice to liquid phase , water . When ice start to melt , the heat supplied to ice is used over the force of attraction between the ice molecules ( H₂O ) . Stronger the force of attraction , more the energy will be required to overcome these forces .
Ice has inter molecular force of attraction as Hydrogen bonds , which can be defined as partially electrostatic attraction present between Hydrogen which is covalently bonded to more electronegative atom ( which has lone pairs like Oxygen , nitrogen , fluorine ) and atom which has lone pair of electrons of other molecule .
Since H₂O molecules have two Hydrogen atoms and one atom Oxygen present in it . Due to present of Oxygen , which is an electronegative atom and have lone pair of electrons ,pulls the electron of hydrogen .There occur partial negative charge on O and partial positive charge on H . Due to presence of partial + and - charge , there occur force of attraction between H of one molecule and O of other H2O molecules , which is known as Hydrogen Bonding.
So options C) Hydrogen bonds are correct .