whAt DoEs thE Author mEAn By "BlACk AnD whitE" in "thErE ArE no gyrEs in his piCturE oF thE worlD, EvErything is EithEr DiABoliCAlly BlACk or CElEstiAlly whitE" .
A．hE mEAns EithEr right or wrong.
B．thEy rEprEsEnt propAgAnDists, philosophErs AnD thE Common pEoplE.
C．hE mEAns thEy ArE thE BAsiC Colours in thE worlD ArounD us.
D．hE mEAns BAD, gooD AnD DouBtFul mAttErs.