Which can cause a stress fracture?

Stress fracture can be caused by "Repitative force or from over use ."

Explanation:

Stress fractures are tiny cracks in bone. It is caused due to jumping and running for long distances. It is common in the weight bearing bones present in the lower leg as well as in foot.

It can be noticed with pain which gets worse with time. Or it may heal during rest. It is mostly seen when people newly start doing exercises, caring heavy objects for long distance. In osteoporosis, stress fractures could be noticed by doing regular activities.  

out of the choices i'd say d the ability to set goals, mainly because to desire to continue you need motivation but it isn't motivation in that part, but setting goals means you have an endgame and you want to reach it which sums up motivation.