Pick up the correct statement from the following: A. The vertical plane containing the zenith, the station of observation and the celestial pole is the observer’s meridian plane B. The angle between the direction of star in vertical plane and the direction of the star in horizontal plane is called the altitude of the star C. The complement of the altitude of star is called the zenith distance of the star D. All the above

The correct answer is D. All the above.

The vertical plane containing the zenith, the station of observation and the celestial pole is the observer’s meridian plane. This is because the meridian plane is the plane that passes through the observer’s zenith, the celestial pole, and the observer’s horizon.

The angle between the direction of star in vertical plane and the direction of the star in horizontal plane is called the altitude of the star. This is because the altitude of a star is the angle between the star’s vertical circle and the observer’s horizon.

The complement of the altitude of star is called the zenith distance of the star. This is because the zenith distance of a star is the angle between the star’s vertical circle and the zenith.

Therefore, all of the statements in the question are correct.