If $$0 < x < \pi$$ and $$\cos x + \sin x = \dfrac{1}{2}$$, then $$\tan x$$ is

A

$$\dfrac{(1 - \sqrt{7})}{4}$$

B

$$\dfrac{(4 - \sqrt{7})}{3}$$

C

$$-\dfrac{(4 + \sqrt{7})}{3}$$

D

$$\dfrac{(1 + \sqrt{7})}{4}$$