Task: Question Answering
Input (English): Question: Average of money that group of 4 friends pay for rent each month is $800.After one persons rent is increased by 20% the new mean is $870.What was original rent of friend whose rent is increased?

 Option A: 800

 Option B: 1400

 Option C: 1000

 Option D: 1100

 Option E: 1200
Output (English): Option B