Answer:
B. Magnitude
Explanation: I just took the test and it said it was magnitude
An astronomical object made up of plasma and are found at a fixed position in the solar system is called a star. An increase in the brightness of the star decreases the magnitude.
Brightness is the property of an object to reflect the light back. It can be said to be used with luminescence. The brightness of the star depends on its position around the planet.
Magnitude is the immensity or the extent and the size of the object located. The magnitude of the stars measures the brightness of the stars and celestial bodies. It depends on the luminosity.
Therefore, option B. magnitude becomes smaller.
Learn more about magnitude and brightness here:
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