The correct answer is A. (6500, 6000).
The A.R.P. (Airport Reference Point) is a fixed point on the ground that is used as a reference for navigation. It is typically located at the center of the runway.
To find the coordinates of the A.R.P., we can take the average of the coordinates of the ends of the runway. The coordinates of the ends of the runway are (5000, 5000) and (8000, 7000). The average of these coordinates is (6500, 6000). Therefore, the coordinates of the A.R.P. are (6500, 6000).
Option B is incorrect because it is the average of the coordinates of the ends of the second runway. The coordinates of the ends of the second runway are (4600, 5100) and (7000, 5300). The average of these coordinates is (5800, 5200).
Option C is incorrect because it is not a valid coordinate.
Option D is incorrect because it is the coordinate of one of the ends of the first runway.