A:CH3CH2Br+NaHS→CH3CH2SH+NaBr
B:CH3I+CH3ONa→CH3OCH3+NaI
C:CH3CH2Cl+CH3ONa→CH3Cl+CH3CH2ONa
D:CH3CH2Cl+CH3CH2ONa→CH3CH2O CH2 CH3+NaCl
台湾居民绝大部分是哪两省移民的后代( )