Like throwing up because it makes sense
A.Musclar Balance Because it helps you with physical health.
Sti stands for Sexually Transmitted Infection. It is referred to sexually transmitted diseases.
D. Regular Exercise has been shown to reduce the physical effects of stress.
A wouldn't be correct because at home, you can find plenty of time to relax.
B would be wrong because it is opinion based and would be extremely difficult, if not impossible to experiment for.
And C would be wrong because mental discipline doesn't necessarily means you can take away stress.
Hope this helps!
~GeeksandNerds