A ring of radius R carries a linear charge density $$\lambda$$ . It is rotating with angular speed $$\omega$$ . The magnetic field at its center is

A

$$ \frac{3 \mu_{0} \lambda \omega}{2}$$

B

$$\frac{\mu_{0} \lambda \omega}{2}$$

C

$$\frac{\mu_{0} \lambda \omega}{\pi}$$

D

$$\mu_{0} \lambda \omega$$