Answer:
All apply.
A) Fossils are impressions of plants or animals embedded in rock and preserved. They may be in the form of a body or trace.
The age of the fossils is determined by the Radioactive carbon dating technique in which the half-life of carbon and found radioactive elements is determined to calculate the age of a fossil.
B) Studying fossil pollen and other fossils helps scientists to learn more about climate change. Based on the evidence these fossils provide, we can find out whether or not climate has changed in the past, and how fast and frequently climate changes occurred.
C) Since the lowest surfaces are the ocean floors, we would expect to find marine fossils to form before terrestrial fossils. As the ocean floors were covered with sediment, we might expect to find fossils of species from low-lying terrestrial areas, followed by fossils of species from higher elevations. This theory was first proposed by Harold W Clark and is called the Ecological Zonation Theory.
D) Fossils tell about the ancient organisms' life and their evolution on earth millions of years ago. Fossils are direct evidence of evolution. It tells about the life found on ancient earth. By studying fossil records palaeontologists reveal the connecting link between different organisms of the past and present.
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