The answer is a. Good luck
Answer:
The unit of measure which should be used to describe the size of the galactic body mentioned in the question is
Astronomical Units.
Explanation:
Trying to measure the size of planets in Kilometers and Miles is futile as the numbers are too enormous.
Astrologists have invented metrics which keep it simple and one Astronomical Unit is equal to 149,597,871 kilometers (92,955 miles).
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They provided water for food and served as transportation waterways