Compute the integral \int_{|z|=r} xdz for the positive sense of the circle in two ways. First, by using a parameter, and second, by observing that x=\frac{1}{2}(z+\frac{r2}{z}) on the circle. Which of the following options correctly describes the two methods of computation?

A) Using a parameter and observing that x=\frac{1}{2}(z+\frac{r2}{z}) on the circle.
B) Using a parameter and observing that x=\frac{1}{2}(z+\frac{r2}{z}) on the circle.
C) Using a parameter and observing that x=\frac{1}{2}(z+\frac{r2}{z}) on the circle.
D) Using a parameter and observing that x=\frac{1}{2}(z+\frac{r2}{z}) on the circle.