When Geologists Conclude That the Grand Canyon Sequence of Rocks

When geologists conclude that the Grand Canyon sequence of rocks was formed through hundreds of millions of years of deposition, mountain building, and erosion, they are basing this conclusion on the principle of ________ which states that ________.

A) catastrophism; most rock formations were created as a result of supernatural processes
B) catastrophism; a single, large flood was responsible for the creation of the rock sequence
C) uniformitarianism; all geologic processes take immense amounts of time to occur and always occur at the same rate
D) uniformitarianism; the geologic processes that operated in the past are the same as those that operate today, and they occurred in accordance with the same laws of nature that are operating today