Heat Is Added to a 1

Multiple Choice

Heat is added to a 1.0-kg solid sample of a material at -200 °C. The figure shows the temperature of the material as a function of the heat added.
-What is the latent heat of fusion of this material?

A) 50 cal/g
B) 100 cal/g
C) 150 cal/g
D) 300 cal/g
E) 450 cal/g