Help please! I will give brainliest if you get the correct answer An astronomer examines an emission line spectrum for a star from data recorded by a spectroscope. There are four lines: two in the blue region, one in the green region, and one in the red region of the spectrum. How does the spectrum obtained from the spectroscope help the astronomer?

A. It helps the astronomer determine that there are 4.32 light years between the star and the Sun.

B. It helps the astronomer determine that the star is two times larger than its neighboring star.

C. It helps the astronomer determine that the star is made mostly of hydrogen.