Answer:
The correct answer is "a fossil of a fish".
Step-by-step explanation:
The law of faunal and floral succession states that based on observation, sedimentary rock strata contains fossilized organisms in a predictable order. According to this law the layer of a rock above an imprint of a shelled animal would likely have a fossil of a fish. This theory is supported by evolutionary evidence of fishes being formed after shelled animals in ancient times.