A crab dies and becomes buried beneath the mud in the bottom of the ocean. The mud fills in tightly around the crab's shell. Over many years, the shell decays and the mud hardens. This leaves a hollow space that is the same shape as the crab's original shell.
A. Amber
B. Mold
C. Cast
D. Imprint
E. Petrified

It is a mold. A mold is a recreation of the cast but is not made from the original features the cast was made up of. Such as mud in the example above. The cast shell was made up of its shell and the mold shell was made from the mud.

Explanation:

answer; a muscle cell, another neuron and a of the above

1. dermis

2. chemical

3. urine

4. viruses

5. antibodies