Task: Question Answering
Input (English): Problem: the compound ratio of 5 : 7 , 3 : 2 and 4 : 5 ? 
Options: a ) 1 : 7 , b ) 6 : 5 , c ) 6 : 7 , d ) 4 : 7 , e ) 6 : 9
Output (English): c