It strengthens your bones to be able to handle large amounts of pressure and weight on your body. I know this isn't related, but when a person breaks their ankle or something else they tend to heal quicker because they're athletes. So one way or another, increasing strength, helps to increase your capacity for exercising.
Individual decision making is more limited than collaborative decision making because as an individual you would only have one or two points of view on the subject as well as knowledge and ideas. If you were to work with more people to decide on something then there would be a good chance that everyone would be able to pitch in ideas and different points of views to overall decide.
I think the answer is b
I hope this helps :)