Option C is correct. An endoskeleton is a skeleton that is on the inside of a body. The endoskeleton develops inside the skin or in the deeper body tissues. The vertebrate endoskeleton is basically made up of two types of tissues (bone and cartilage).
The human skeleton is an endoskeleton that consists of 206 bones in the adult. It has 5 major functions: offering guide to the body, storing minerals and lipids, producing blood cells, protecting interior organs, and permitting for movement.
Mammals, reptiles, birds, fish and amphibians are vertebrates with endoskeletons (skeletons inside their bodies). Their skeletons furnish assist and safety and help them to move. Insects, spiders and shellfish are some of the invertebrates that have exoskeletons.
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