Step 1: Equation of normal to the parabola.
The equation of the normal to the parabola \( y^2 = 4ax \) at any point \( (x_1, y_1) \) is derived, and solving for \( p \) and \( q \) yields the equation \( p^2 + pq + 2 = 0 \).
Step 2: Conclusion.
Thus, the correct answer is option (A).