A) the exchange of gases throughout the body
Life expectancy is a generalization for a specific generation or peoples in a given era. People born between the late 90s to early 2000s have a greater live expectancy than say peoples 300 years ago. We are “expected” to live until about our late 70s, early 80s because we as a society have the means to keep us living longer. Someone who dies before that window, may have had some complications with their health that prevented them the estimated age.
The answer is D since doing more physical activity creates more energy and help people benefit from the exercise
Answer:
metabolism, mood, reproduction.
Explanation: