whiCh oF thE Following BEst summArizEs thE mAin iDEA oF thE pAssAgE
A．mEChAnizAtion oF work hAs littlE ChAngED thE ConDitions oF womEn.
B．mEChAnizAtion rEvolutionizEs A soCiEty's CustomAry rolEs oF its mEmBErs.
C．mEChAnizAtion oF work CrEAtEs nEw joBs thAt DiD not Exist prEviously.
D．womEn's work hAs ChAngED ConsiDErABly in thE pAst 200 yEArs.