A loop carrying current I lies in the x-y plane as shown in the figure. the unit vector $$\hat{k}$$ is coming out of the plane of the paper. the magnetic moment of the current loop is :

A

$$a^2I\hat{k}$$

B

$$\left(\frac{\pi}{2} + 1\right)a^2 I\hat{k}$$

C

$$-\left(\frac{\pi}{2} + 1\right)a^2 I\hat{k}$$

D

$$(2 \pi + 1)a^2 I \hat{k}$$