The modulus of $$1 + \cos \alpha + i \sin \alpha$$ is

A

$$2 \sin \frac {\alpha}{2}$$

B

$$2 \cos \frac {\alpha}{2}$$

C

$$\sin^2 \frac {\alpha}{2} - 1$$

D

$$\cos^2 \frac {\alpha}{2} - 1$$