A、right-hAnDED pEoplE ArE supErior to lEFt-hAnDED pEoplE.
B．right-hAnDEDnEss is DEtErminED gEnEtiCAlly, But lEFt-hAnDEDnEss is lEArnt.
C．ABout 18% oF iDEntiCAl twins ArE lEFt-hAnDE
D、
D、sCiEntists hAvE not yEt rEAChED AgrEEmEnt on thE CAusEs oF lEFt-hAnDEDnEss.