Task: Question Answering
Input (English): Problem: a garrison of 300 men had a provision for 31 days . after 28 days 280 persons re - enforcement leave the garrison . find the number of days for which the remaining ration will be sufficient ? 
Options: a ) 45 days , b ) 55 days , c ) 35 days , d ) 25 days , e ) 40 days
Output (English): a