Please explain why chosen the answer A.

4. The system of compound pulleys depicted in the diagram is utilized to transport loads with a mechanical advantage of 10. If the load is between 50 and 250 kg, and the motor can provide a torque of 3 to 30 N.m, and the large pulley has a radius of 25 cm, and the motor's driven shaft has a radius of 5 cm. What should the small pulley's radius r be? -25 cm 5 cm load motor A. 2.50 cm B 5.00 cm C 8.30 cm D. 16.66 cm