According to maximum shear stress theory, the maximum shear stress in the shaft is

• A. <img src="/_files/images/mechanical-engineering/machine-design/579-267-1.png">
• B. <img src="/_files/images/mechanical-engineering/machine-design/579-267-2.png">
• C. <img src="/_files/images/mechanical-engineering/machine-design/579-267-3.png">
• D. <img src="/_files/images/mechanical-engineering/machine-design/579-267-4.png">