A Copper Bar (D = 10 Mm, E = 110 $73 \mathrm{MPa}$

A copper bar (d = 10 mm, E = 110 GPa) is loaded by tensile load P = 11.5 kN. The maximum shear stress in the bar is approximately: (A) $73 \mathrm{MPa}$
(B) $87 \mathrm{MPa}$
(C) $145 \mathrm{MPa}$
(D) $150 \mathrm{MPa}$