Fossils of the simplest organisms are found in the oldest rocks, and fossils of more complex organisms are in the newest rocks. Which of the following supports this?

Species have evolved over time, according to Darwin's theory, through the process of natural selection, in which organisms with advantageous traits are more likely to survive and reproduce. This process results in the gradual accumulation of changes in a species and the development of new species over millions of years.

As these species would have evolved earlier in Earth's history, one would expect to find fossils of the simplest organisms in the oldest rocks. One would expect to find fossils of these species in younger rocks as time passed and more complex organisms evolved.

The scientific field of palaeontology, which studies fossils and the history of life on Earth, backs up Darwin's theory of evolution. 

Lamarckism, on the other hand, is a debunked evolutionary theory that holds that traits acquired during an organism's lifetime can be passed down to offspring. 

The study of fossils or the history of life on Earth has nothing to do with the law of dominance.