[单选题]
The heat required to change y6j1 jw2fwv0ka substance from the liquid 26m ob 8+ oyh:5jug mjseqa99cto the vapor state is referred +98b6:su5yhgm2 o jm9ceoq jato as the
A. heat of fusion.
B. heat of vaporization.
C. heat of evaporation.
D. heat of condensation.
