Task: Question Answering
Input (English): Problem: x , a , z , and b are single digit positive integers . x = 1 / 5 a . z = 1 / 5 b . ( 10 a + b ) – ( 10 x + z ) could not equal 
Options: a ) 36 , b ) 33 , c ) 44 , d ) 64 , e ) 56
Output (English): b