[单选题]
The heat required tob:iub+ rksj:* x smwtjg,uf/+ yqa9 63 c zd90z 5ax9j (ieawhadjs 2( sj;g,gv4hange a substance from the liquid to the vapor state is referred to a(haajx d9e , i4;(jawsgv9zs02gjd z5s the
A. heat of fusion.
B. heat of vaporization.
C. heat of evaporation.
D. heat of condensation.
