In the beginning, ice and water are in equilibrium, hence the temperature would be zero. On heating the mixture, the temperature remains the same till all the ice melts. This heat gets used up in changing the state by overcoming the forces of attraction between the particles. As this heat energy is absorbed by ice without showing any rise in temperature, it is considered that it gets hidden into the contents of the beaker and is known as the latent heat*. On further heating, the temperature of the water would increase. Therefore, the correct option is (d).

* Latent heat of fusion is the amount of heat energy required to change 1 kg of solid into liquid at its melting point.