I looked it up and it should be D. Nerve cells :)
Your answer is c: hydrogen bonds
Answer:
1. Support
2. Protection
3. Movement
4. Supply & Storage
Explanation:
1. Support : It provides a framework to support the organs and tissues of the body.
2. Protection: It protects our internal organs. The skull protects the brain; the thorax (sternum, ribs and spine) protects the heart, lungs and other viscera (organs within the thorax).
3. Movement: It provides a framework for muscles to attach. Then when the muscles contract they pull on the bones of the skeleton, which act like levers to create movement.
4. Supply & Storage: The bones that make up the skeleton are a source of both red blood cells (which transport oxygen) and white blood cells (which fight infection), which are formed within the bone marrow.
I think C) availability of water is your best answer because alot of organisms count on water as a major resource because they need it to survive so a lack or a gain in the amount of water will majorly effect an ecosystem.
