Answer:
Global warming
Explanation:
The environmental problems like global warming, acid rain, air pollution, urban sprawl, waste disposal, ozone layer depletion, water pollution, climate change and many more affect every human, animal and nation on this planet.
A. The balance needed to hold a handstand without falling.
Skill-related fitness is something that your body needs to be trained to do and need focus to complete. The other answer options are your body's physical capability rather then something that takes skill and needs practice, such as balance.