If $$270^\circ < \theta < 360^\circ$$ and $$\cot \theta = -\sqrt{3}$$ then $$\cos \theta =$$

A

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

B

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

C

$$-\frac{\sqrt{3}}{2}$$

D

$$-\frac{1}{\sqrt{3}}$$