Task: Question Answering
Input (English): Problem: if 20 men can build a water fountain 56 metres long in 21 days , what length of a similar water fountain can be built by 35 men in 3 days ? 
Options: a ) 10 m , b ) 14 m , c ) 17 m , d ) 19 m , e ) 20 m
Output (English): b