The correct answer is A. A law
Step-by-step explanation:
In science, a law describes a phenomenon or event that always occurs under specific circumstances, and therefore it is constant. Due to this, laws are created based on multiple experiments or observations that lead to the same result. Also, a law only describes a phenomenon but does not explain why this occurs, which belongs to scientific theories.
The statement "traits are passed from parents to offspring independently of one another" by Mendel is a law because it describes a proven and constant phenomenon in genetics. Also, this is the result of the multiple experiments made by Mendel that showed the same result in terms of genetics.