Task: Question Answering
Input (English): Problem: the value of ( ( x – y ) ³ + ( y - z ) ³ + ( z – x ) ³ ) / ( 15 ( x – y ) ( y – z ) ( z – x ) ) is equal to : 
Options: a ) 0 , b ) 1 / 12 , c ) 1 , d ) 1 / 5 , e ) 1 / 3
Output (English): d