"the force with which a solvent moves across a semipermeable membrane from a higher to a lower concentration"

Option C."Straddle stretch"

Explanation:

Upper body stretch is a type of stretching which involves movement of upper body parts such as neck, shoulder, arms, chest, and back. Therefore arm circles, trunk twist, and triceps stretch are the examples of Upper body stretch.

Whereas, Straddle Stretch also called Upavistha Konasana, is a seated stretching pose which involves movement of lower body (legs). it involves stretching of legs out as wide as possible and flexing of hips and toes upwards and bending hands touching the floor, followed by deep breath.

Hence, straddle stretch is not an upper body stretch.