What can the scientist conclude from this finding ?
a. all the fossils in this diagram are more than 540 million years old.
b. fossil in layer 2 are less than 540 million years old.
c. fossils from layer 9 are the newest in the diagram
d. fossil in layer 6 are less than 540 million years old.

Option D, Fossil in layer 6 are less than 540 million years old

Explanation:

In any fossil deposition, the youngest of fossils lies at the topmost layers while all other layers below it are much older than it.

Here, layer 1 lies at the bottom and layer 13 lies at the top. Thus, layer 1 is the oldest and layer 13 is the youngest fossil.

In the question , it is given that index fossil of age 540 million years old are found at the layer 5, therefore all layer lying above it will be less than 540 million years.

Therefore, option D is correct.

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