Answer: multi-cellular bodies
Explanation: All animals are multi-cellular. This means that they are made up of many cells/cellular systems. Single-celled organisms, on the other hand, are not considered animals. Those would mostly be too tiny to see without the aid of a microscope tool. The other answer choices would not fit, because not all animals have bones (endoskeletons or exoskeletons). Also, only some animals are cold blooded, which is what the last answer choice has to do with.
The correct answer is mitochondria
Earth ? Or nature witch one are you getting at
Answer:
Explanation:a
majority of an atom's mass is found its protons and neutrons, subtracting the number of protons (i.e. the atomic number) from the atomic mass will give you the calculated number of neutrons