D. <span>social activities, such as team sports, promote exercise. this is the only question in which it says why as in promoting exercise, the other answers do not specify</span>
The answer is general decrease
As we got older, our metabolic system will tend to become slower. This makes older people tend to have lower heart rate compared to younger ones because you need your blood to circulate the oxygen all over your body if your body is doing a metabolism process.
The immune system<span> is a network of cells, tissues, and organs that work together to defend the body against attacks by foreign invade. These are primarily microbes—tiny organisms such as bacteria, parasites, and fungi that can cause infections.</span>
Answer:
How many doughnuts are sold each year in the three largest countries in the world?
Explanation:
This is the biggest problem with an easy resoloution :)) I hope this helps!