C. Tracking your flexibility over time as you train. There are no requirements on how flexible you need to be and there is no correlation of your length of life or muscle strength with how flexible you are.
<h3>Answer: </h3><h2>(C) Tracking your flexibility improvements over time</h2><h3>Explanation: </h3>
There is no apparatus for measuring body's flexibility, as this factor is something that an individual feels by looking at the changed posture and performance. The benefit that one gets from looking at one self is of tracking his/her own rate of flexibility over a period of time and see improvements and changes themselves.
