In the figure, circle \(O\) has center \(O,\) diameter \(AB\) and a radius of \(5.\) Line \(CD\) is parallel to the diameter. What is the perimeter of the shaded region?

A. \(\dfrac53 \pi +5\sqrt3\)

B. \(\dfrac53 \pi +10\sqrt3\)

C. \(\dfrac{10}3 \pi +5\sqrt3\)

D. \(\dfrac{10}3 \pi +10\sqrt3\)

E. \(\dfrac{10}3 \pi +20\sqrt3\)

Answer: D

Source: Manhattan GMAT