Answer: Teenagers by nature have a tendency to be more reckless and allowing them to play dangerous sports is a risk.
Step-by-step explanation:
After this you need to find some sources to draw off, maybe throw in a statistic about how people in adolescence's brains aren't fully developed yet and can lead to more risktaking. Not sure what your argumentative stand is on this but you need to summarize your points from earlier without saying exactly the same thing.