If $$x + \frac{1}{x} = \frac{1}{\sqrt{7}}$$, then what is the value of $$(x^2 + 1) \div \left[x^4 + \left(\frac{1}{x^2}\right)\right]$$?

A

$$2\sqrt{7}$$

B

$$3\sqrt{7}$$

C

$$\frac{1}{2}$$

D

$$\frac{1}{4}$$