Pick up the correct statement from the following: A. The horizontal direction of the pole is called astronomical north B. The angle between the direction of true north and the direction of a survey line is called astronomical bearing C. The astronomical bearing is generally called azimuth D. All the above

The correct answer is D. All of the above.

• Astronomical north is the direction of the north celestial pole, the point in the sky directly above the Earth’s North Pole.
• Astronomical bearing is the angle between the direction of true north and the direction of a survey line.
• Azimuth is the angle between the north direction and the direction of a line, measured clockwise from north.

The astronomical bearing is generally called azimuth, but it is important to note that the two terms are not synonymous. Astronomical bearing is a specific type of azimuth, and there are other types of azimuths as well. For example, magnetic azimuth is the angle between the direction of true north and the direction of a survey line, as measured by a compass.