A rainbow is formed when a ray of sunlight passes through a spherical raindrop. Then the total angle through which the ray deviates is ($$i$$ and $$r$$ denote the angles of incidence and of refraction respectively)

A

$$2i - 4r$$

B

$$\pi + 2i - 4r$$

C

$$2(i - r)$$

D

$$2(\pi + i - 2r)$$