The correct answer is A. Leaves were trapped between layers of sediment millions of years ago, causing the imprint.
This explanation is correct because it explains the formation of fossils in sedimentary rock. Many fossils have been found that can be dated using processes such as half-life and radiometric dating, and these fossils also serve as evidence for evolution by showing the progress of species over time. Fossils are made either as imprints from living things or as skeletons of deceased organisms, both of which occur in sedimentary rock which reveal rock strata, or layers of very old rock that have been pushed down by newer layers. Therefore, your answer is A.
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