Your reasoning makes sense in the context of how theories and laws are defined in science. However, it's important to consider that both statements relate to scientific concepts.
A scientific theory is typically a well-substantiated explanation of some aspect of the natural world that is based on a body of evidence and can be tested and modified as new evidence emerges. In this context:
- Statement A refers to the explanation of how dominant and recessive genes work in inheritance, which is indeed a concept tied to genetic theory.
- Statement B, on the other hand, references the elliptical orbits of planets, which is derived from Kepler's laws of planetary motion, a foundational principle in astronomy.
While you are correct that Statement A involves an explanatory aspect that fits with the nature of a scientific theory, it's worth noting that both statements discuss scientific principles. However, A tends to align more closely with the idea of a theory because it explains the underlying mechanism of genetic inheritance.
So, if we are specifically looking for a detailed explanation of a phenomenon, A is indeed a better fit for describing a scientific theory.