Risky behaviors and negative health outcomes have negative effects on young people that are very well known. They lead to personal, social and economic problems. They are associated with mortality, namely through accidents, violence and crime. Loss of fame and fortune are some of them, but the most important is the loss of health and ultimately life. It can lead to negative outcomes such as low educational attainment, being bullied and emotional health problems.
A or B are both the best options in this case, but B is the best option overall because if he is interested in an activity, then he will have more motivation.