The velocity ratio of a differential wheel and axle with D as the diameter of effort wheel and d1,and d2 as the diameters of larger and smaller axles respectively, is

• A. <img src="/_files/images/mechanical-engineering/engineering-mechanics/37-161-1.png">
• B. <img src="/_files/images/mechanical-engineering/engineering-mechanics/37-161-2.png">
• C. <img src="/_files/images/mechanical-engineering/engineering-mechanics/37-161-3.png">
• D. <img src="/_files/images/mechanical-engineering/engineering-mechanics/37-161-4.png">