B.exercise because static stretch and rest aren't physical which wouldnt move muscles
The parent might put the child in a club so the child can get used to helping others or being help which will help the child's self-esteem
I mean, find what you want to work on when feeling mentally unstable. I guess just make a goal to what you want to achieve when doing this.
Fitbits, smart watches and pe'dometers can monitor heart-rate.
