If $$x = 8\left(\sin \theta + \cos \theta\right)$$ and $$y = 9\left(\sin \theta - \cos \theta\right)$$, then the value of $$\frac{x^{2}}{8^{2}} + \frac{y^{2}}{9^{2}}$$ is:

A

4

B

6

C

8

D

2