If $$\theta$$ be a positive acute angle and $$\cos^4 \theta - sin^4 \theta = \frac {2}{3},$$ then the value of $$1 - 2 sin^2 \theta$$ is

A

$$\frac {1}{3}$$

B

$$\frac {2}{3}$$

C

$$1$$

D

$$\frac {4}{3}$$