Radius of the Mohr circle of stress numerically equal to

Correct option is B

​$$\begin{aligned}&\textbf{1. Mohr's Circle Parameters:} \\&\quad \text{For a 2D stress state } (\sigma_x, \sigma_y, \tau_{xy}), \text{ the radius } (R) \text{ of Mohr's circle is:} \\&\quad R = \tau_{\text{max}} = \sqrt{ \left( \frac{\sigma_x - \sigma_y}{2} \right)^2 + \tau_{xy}^2 } \\[1em]&\quad \text{This represents the \textbf{maximum shear stress} in the material.} \\[1em]&\textbf{2. Key Points:} \\&\quad \text{The radius } (R) \text{ is always equal to } \tau_{\text{max}}. \\&\quad \text{The center of the circle is at } \left( \frac{\sigma_x + \sigma_y}{2},\ 0 \right).\end{aligned}$$​​