Task: Question Answering
Input (English): Problem: a and b complete a work in 7 days . a alone can do it in 14 days . if both together can do the work in how many days ? 
Options: a ) 4.6 days , b ) 4.78 days , c ) 5.65 days , d ) 3.77 days , e ) 5.75 days
Output (English): a