I think it's most likely D because when I googled the definition it said something about gas so yeah
Answer:
The skull protects the brain from any direct damage and the vertebrae helps keep the nerves in the spine in place and protected from damage. So the central nervous system is protected by the vertebrae and the skull.
Life processes depend in large part on solutions. Oxygen from the lungs goes into solution in the blood plasma, unites chemically with the hemoglobin in the red blood cells, and is released to the body tissues. The products of digestion also are carried in solution to the different parts of the body. The ability of liquids to dissolve other fluids or solids has many practical applications. Chemists take advantage of differences in solubility to separate and purify materials and to carry out chemical analysis. Most chemical reactions occur in solution and are influenced by the solubilities of the reagents. Materials for chemical manufacturing equipment are selected to resist the solvent action of their contents.
<em>Five benefits of physical activity: </em>
1. It strengthens the body. - Physical
2. It prevents illness. - Physical and Emotional
3. It improves brain function. - Mental
4. It increases energy level. - Mental and Physical
5. It makes you feel happier. - Emotional and Social
Physical exercise is beneficial to all aspects of human existence whether physically, mentally, emotionally, socially, or spiritually. Once you are physically healthy, the rest follows. Everything is interconnected.