In mentioning "trilobite," the author is making which of the following points？A．Fossils ca

In mentioning "trilobite," the author is making which of the following points？

A．Fossils cannot be found in more than one rock stratum.

B．Faunal succession can help put rock layers in relative temporal sequence.

C．Faunal succession cannot be applied to different strata composed of the same kind of rock.

D．The presence of trilobite fossils makes it difficult to date a rock.

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