The ability of an animal to maintain a stable internal environment is called homeostasis.
The correct answer is the one that shows a bone having the most porous appearance inside.
Osteoporosis is a disease of the different types of bone tissue that make up bone ("cortical bone" and "trabecular bone").
It is a disease that is related to a decrease in the amount of bone tissue in the bones and / or an alteration of its structure: thinning of the cortex and bone trabeculae that become porous.
The cause is an imbalance between the deficit activity of osteoblasts and normal osteoclastic bone resorption.
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There will be less young organisms and way more older ones - this will put the population into decline