The integral \(\oint _c \left( {ydx - xdy} \right)\) is evaluated along the circle \({x^2} + {y^2} = \frac{1}{4}\) traversed in counter clockwise direction. The integral is equal to

The integral \(\oint _c \left( {ydx - xdy} \right)\) is evaluated alo

1.	The integral \(\oint _c \left( {ydx - xdy} \right)\) is evaluated along the circle \({x^2} + {y^2} = \frac{1}{4}\) traversed in counter clockwise direction. The integral is equal to
A.	0
B.	\(- \frac{\pi }{4}\)
C.	\(-\frac{\pi }{2}\)
D.	\(\frac{\pi }{4}\)
Answer» D. \(\frac{\pi }{4}\)