When Heat Energy Is Added to a Solid and Liquid

When heat energy is added to a solid and liquid mix at the melting point, the temperature does not increase, as illustrated by horizontal line C. Which of the statements below best describes what happens to the heat energy added to the solid and liquid?

A) It increases the kinetic energy of the molecules.
B) It decreases the kinetic energy of the molecules.
C) It breaks the intermolecular forces between the molecules.
D) It makes new intermolecular forces between molecules.
E) It just passes through the solid and liquid, which is why the temperature does not increase.