Answer:
option A
Step-by-step explanation:
The correct answer is option A
The binary star system is the system in which two stars are continuously orbiting each other,
In the eclipsing binary system, two stars revolve about there center of mass and in this system one one-star eclipse another star.
Spectroscopic binary stars are found from the observation of radial velocity and the brighter member of such binary can be seen to have continuously changed the wavelength and periodic velocity.
When the pairs of stars appear to change position in the sky then it is known as visual binary.