Task: Question Answering
Input (English): Problem: a contractor undertook to do a piece of work in 15 days . he employed certain number of laboures but 5 of them were absent from the very first day and the rest could finish the work in only 20 days . find the number of men originally employed ? 
Options: a ) 25 , b ) 20 , c ) 19 , d ) 23 , e ) 18
Output (English): b