Is it best to be very flexible, moderately flexible, or not flexible (muscle stiffness) when participating in sport/exercises? Explain.

I would assume the answer to be very flexible, or at least moderately flexible, but I don't know for sure. It would be greatly appreciated if someone with more experience could help clear this up for me.

Does the weight loss program have practical significance? a. no, the program is not practically significant because the results are likely to occur even if the weight loss program has no effect. b. yes, the program is practically significant because the results are too unlikely to occur by chance. c. yes, the program is practically significant because the amount of lost weight is large enough to be considered practically significant. d. no, the program is not practically significant because the amount of weight lost is trivial.