A and B are standing at a distance of 20 km from each other on a straight East-West road. A and B start walking simultaneously eastwards and westwards respectively and both cover a distance of 5 km. Then A turns to his left and walks 10 km. B turns to his right and walks 10 km at the same speed. Then both turn to their left and cover a dis¬tance of 5 km at the same speed. What will be the distance between them?

• A. 10km
• B. 30km
• C. 20km
• D. 25km