Bhanu takes a total of 6 hours 50 minutes in walking a distance and running back to same place where she started. She could walk both ways in 8 hours 30 minutes. The time taken by her to run both ways is :

• A. 5 hours 25 min
• B. 5 hours 15 min
• C. 5 hours 10 min
• D. 5 hours 45 min