I think it is all of the above but you might want a second opinion.
Answer:
C) Mass
Explanation:
Mass is made up by the amount of protons, neutrons, and electrons in an object. Mass is essentially the capacity of an object, which many times is mistaken for weight.
Shape, color, and size are all common ways to determine the species of the bird, when only looking at the egg.
Hope this helps! :)
An Organ. Why does the answer need to be 20 characters long?
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