Using Green's Theorem, Calculate the Area of the Indicated Region $\le$

Multiple Choice

Using Green's Theorem, calculate the area of the indicated region.
-The circle r(t) = ( 10 cos t) i + ( 10 sin t) j, 0 $\le$ t $\le$ 2 $\pi$

A) 10 $\pi$
B) 2 $\pi$
C) 20 $\pi$
D) 100 $\pi$