From experience with my best friend, I´d say C.
Do they work you mean?? Different variations of the position of your hands hits different muscle parts. Like doing push-ups with your hands far apart hits more of the chest area. Doing them with your hands close hits more of your triceps. I personally like them close.
The best answer for this question would be:
biological and social
Medical anthropologist need to understand the source of their biological heritage and ofcourse the system of their bodies in order to understand their suffering. Social factor is also important, because it can tells them the source of their suffering.
