If the equation $$k(21x^2 + 24) + rx + (14x^2 - 9) = 0$$
$$k(7x^2 + 8) + px + (2x^2 - 3) = 0$$ have both roots common, then the value of $$\frac{p}{r}$$ is:

A

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

B

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

C

$$\frac{4}{3}$$

D

$$\frac{7}{5}$$