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Which one of the following sedimentary rocks is organically formed?

Options

  1. AShale
  2. BChert
  3. CHalite
  4. DChalk

Correct answer

D. Chalk

Step-by-step solution

Chalk is a variety of limestone composed mainly of calcium carbonate derived from the shells of tiny marine animals known as foraminifera and from the calcareous remains of marine algae known as coccoliths. Chalk forms from a fine-grained marine sediment known as ooze which are organic debris.

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