At the melting point temperature of ice,
both ice and water are present.
Explanation for the correct option:
c) both ice and water are present:
At the melting point temperature of ice, both water and ice are present because the melting point and freezing point of a substance are the same temperature. So melting point and freezing point of water is 00C.
Explanation for the incorrect options:
Since at the melting point temperature of ice, both water and ice are present, a) only ice is present, b) only water is present and d) none of these is correct are incorrect.
Hence, option (c) is correct. At the melting point temperature of ice, both ice and water are present.