Answer:
The correct answer is the option 1: Parallax
Step-by-step explanation:
Parallax is the name given, in the field of physics, to the term that refers to the alternation or displacement in the apparent position of an object that is being watched between two different lines of sight and being measured at the same time by the angle of those two lines. In addition, that statement declares the well known ''principle of parallax'', which is used by the astronomers to measure large distances, such as the example of the question of the apparent movement of a star used to measure its distance from the Earth.