B. Shrimp burrow.
Explanation:
A trace fossil is a fossil left by the animal, such as a foot print or a burrow. It is not part of the actual animal.
Answer : The correct answer is, Halide hydrocarbon.
Explanation :
Freon : Freon are the simple aliphatic organic compounds which may contains fluorine, carbon, hydrogen, chlorine or bromine. So, they are a type of chlorofluoro carbons (CFCs).
They are considered as refrigerants which are used in air-conditioning and refrigeration system.
