The equation for line q is y = mx + b where m is the slope and b is the y-intercept. Since the line passes through the point (4,6) and (0,6), we can find the slope by using the formula m = (y2 - y1) / (x2 - x1) = (6 - 6) / (4 - 0) = 0.
Since the line is perpendicular to line q, the slope of the new line is the negative reciprocal of 0, which is undefined. Therefore, the new line is a vertical line, and the equation is in the form x = a constant. Since the line passes through the point (-2,3), the equation is x = -2. Therefore, the answer is A: x = -2.