A policeman starts to chase a thief. When the thief goes 10 steps the policeman moves 8 steps. 5 steps of the policeman is equal to 7 steps of the thief. The ratio of the speeds of the policeman and the thief is :

• A. 25 : 28
• B. 25 : 56
• C. 28 : 25
• D. 56