I believe it’s a chromosome.
The Answer Would Be
B. <span>the similarities in the body systems such as the nervous and circulatory systems
Hope This Helps
Plz Mark Branliest
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Because you cannot test it or observe it.
A scientific theory are created through the scientific method, in the scientific method you need to be able observe it and experiment.
Aero is the prefix for oxygen or air
Aerobic= needs air
Anaerobic=no air needed