The answer to this is A. Puberty.
It depends, cluster A personality disorders are described as erratic and odd, cluster B as dramatic and erratic, and cluster C as anxious and fearful.
Participating in extreme sports can help your cardiovascular system work properly and better because extreme sports usually are very taxing in terms of being an aerobic sport which also puts a lot of burden on the aerobic system. Another benefit would be not so health-related but more personal; doing extreme sports and being close to death - which can hppen - makes one more appreciative and aware of life and death.
