Task: Question Answering
Input (English): Question: A and B can do a piece of work in 6 days. With the help of C they finish the work in 4 days. C alone can do that piece of work in?

 Option A: 10 DAYS

 Option B: 20 DAYS

 Option C: 25 DAYS

 Option D: 15 DAYS

 Option E: 45 DAYS
Output (English): Option B