Task: Question Answering
Input (English): Problem: working together , wayne and his son can shovel the entire driveway in three hours . if wayne can shovel two times as fast as his son can , how many hours would it take for his son to shovel the entire driveway on his own ? 
Options: a ) 4 , b ) 3 , c ) 8 , d ) 9 , e ) 12
Output (English): b