A point on the parabola $$y^2 = 18x$$ at which the ordinate increases at twice the rate of the abscissa is

A

$$(2, 4)$$

B

$$(2, -4)$$

C

$$\left(\frac{-9}{8}, \frac{9}{2}\right)$$

D

$$\left(\frac{9}{8}, \frac{9}{2}\right)$$