To understand when the wings begin to melt in the story of Icarus, we need to analyze the stages of the plot. The exposition introduces the characters and setting, explaining why Icarus and his father are trapped and how they plan to escape. The rising action involves Daedalus constructing the wings. The climax is the turning point of the story, which occurs when Icarus flies too close to the sun, causing the wax on his wings to melt. This moment is the most intense part of the story, leading to Icarus's fall. The falling action and resolution follow, but the melting of the wings specifically happens during the climax. Therefore, the correct answer is C.