During the melting of a slab of ice at at atmospheric pressure: This question ha

During melting at constant temperature (273 K), ice absorbs latent heat from the surroundings, increasing the internal energy of the ice-water system. The volume decreases upon melting (ice is less dense than water), so the atmosphere does positive work on the system (option B is also correct), but the internal energy increase is a direct consequence of the first law of thermodynamics (ΔU = Q - W, where Q > 0 and W < 0, so ΔU > 0).