The foundation for relative dating is the principle that deeper rock strata are generally older than the ones found closer to the surface. This is known as the principle of superposition. According to this principle, in undisturbed layers of rock, the ones at the bottom formed first, while the ones at the top formed more recently. By studying the order and sequence of rock layers, geologists can estimate the relative ages of the rocks and the fossils they contain.
Option B ("Deeper rock strata are older") is the correct answer as it correctly describes this fundamental principle of relative dating.
