$$PA$$ and $$PB$$ are two tangents to a circle with centre $$O$$. from a point $$P$$ outside the circle. $$A$$ and $$B$$ are points on the circle. If $$\angle APB = 40$$°, then $$\angle OAB$$ is equal to:

A

20°

B

40°

C

25°

D

50°