The correct answer that would answer the given question above would be EXPERIMENTATION. The scientific method uses observation to gather information, and to answer the questions based on the information gathered, this would involve experimentation. This is the testing of the information so that it would given a clear evidence on the answer. Hope this answer helps.
What do you mean by responsible? Do you want to know the genetics behind it, what the surface markers do, or why they are metically important? I think I can help.
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<span>The celestial sphere is a coordinate system that uses the Earth as a reference. Declination indicates how far north or south from the celestial equator an object is. Right ascension indicates how far east or west from the vernal equinox an object is.</span>
