Task: Question Answering
Input (English): Problem: in a certain village , 200 litres of water are required per household per month . at this rate , if there are 5 households in the village , how long ( in months ) will 2000 litres of water last ? 
Options: a ) 9 , b ) 5 , c ) 6 , d ) 2 , e ) 4
Output (English): d