IF $$a + b = p, ab = q$$, then $$(a^4 + b^4)$$ is equal to:

A

$$p^4 - 2p^2q^2 + q^2$$

B

$$p^4 - 4p^2q^2 + 2q^2$$

C

$$p^4 - 4p^2q + q^2$$

D

$$p^4 - 2p^2q + 2q^2$$