If $$2x^{2}+5x+1=0$$, then one of the values of $$x - \frac{1}{2x}$$ is:

A

$$\frac{\sqrt{17}}{2}$$

B

$$\frac{13}{2}$$

C

$$\frac{5}{2}$$

D

$$\frac{\sqrt{13}}{2}$$