Two plane mirrors $$M_1$$ and $$M_2$$ have their reflecting faces inclined at $$\theta$$. Mirror $$M_1$$ receives a ray $$AB$$, reflects it at $$B$$ and sends it as $$BC$$. It is now reflected by mirror $$M_2$$ along $$CD$$, as shown in the figure. Total angular deviation $$\delta$$ suffered by the incident ray $$AB$$ is

A

$$\delta=90^\circ+2\theta$$

B

$$\delta=180^\circ+2\theta$$

C

$$\delta=270^\circ-2\theta$$

D

$$\delta=360^\circ-2\theta$$